Liu, Jian. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 127-152). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstracts also in Chinese.

Zhang, Yang. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2013. / Includes bibliographical references (leaves 147-169). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese.

活性氧在內皮細胞生理發展比如細胞生長增殖和病理中起到非常重要的作用。在病理條件下，活性氧在血管功能失調和重構起到關鍵作用。氧化應激現在被認為存在於多種形式的心血管疾病中。諸多證據表明著活性氧誘導的心血管系統中很多功能異常之前會伴隨有細胞內鈣離子濃度的上升。 / 在本論文的第一個部分，我比較了活性氧在大血管（主動脈）和小血管（腸系膜動脈）的內皮細胞裡引起的鈣應激的相似和差異之處。在這兩種細胞中，活性氧均可引起細胞內鈣離子濃度的上升。這種鈣離子濃度增加可被磷酸酯酶C (PLC) 的抑製劑U73122或者磷酸肌醇受體 (IP₃R) 抑製劑 （Xestospongin C， XeC）大幅度的減弱。此外，用過氧化氫預處理後的細胞會降低細胞對ATP的鈣應激反應。這種鈣應激反應的抑制可能是由於過氧化氫引發的鈣庫流失。令人關注的是，腸系膜動脈的內皮細胞對過氧化氫的作用更為敏感。次黃嘌呤 (hypoxanthine; HX) 加上黃嘌呤(xanthine; XO) 也能引起這兩種內皮細胞鈣離子濃度的上升，而這種鈣離子的增加源於超氧陰離子而不是氫氧離子。在腸系膜動脈的內皮細胞中，過氧化氫在此事件中起到的作用明顯比在主動脈細胞大。總之，過氧化氫可以引起大血管和小血管的內皮細胞裡磷酸酯酶C-磷酸肌醇受體依賴的鈣應激反應。而這種鈣應激後的鈣庫耗竭會對ATP引起的鈣應激起作用。綜上所述，小血管的內皮細胞的鈣應激比大血管的內皮細胞對過氧化氫更為敏感。 / 基於以上的結果，在第二部分的內容中，我們以培植的微血管內皮細胞系（H5V）為小血管內皮細胞的模型，研究了TRPM2通道在過氧化氫誘導的的鈣應激和凋亡中的作用。TRPM2是表達在動物是血管內皮組織中的氧化敏感的和陽離子無選擇性通道。我們開發了TRPM2通道的抑制性抗體 (TM2E3)，這種抗體可以結合到TRPM2通道的離子孔道的E3區域。對H5V細胞進行TM2E3的預處理後，可以降低細胞對過氧化氫刺激下的鈣離子的增加。用TRPM2特異的短發卡核糖核酸 （shRNA）也有同樣的抑制反應。我們用了3種方法來檢測過氧化氫誘導的細胞凋亡：四甲基偶氮唑盐（MTT）檢測，脫氧核糖核酸凋亡片段的檢測和4,6-联脒-2-苯基吲哚(DAPI) 核染色。基於以上的試驗結果，TM2E3 和TRPM2特異的shRNA都表現出了對過氧化氫引起的細胞凋亡的保護作用。相反，在細胞中過表達TRPM2會導致過氧化氫引起的鈣離子濃度上升的增加和細胞凋亡程度的加重。 這些發現強有力的證明了TRPM2 介導了過氧化氫引起的鈣離子濃度的上升和細胞凋亡。此外，我們還研究了TRPM2激活後的下游事件：半胱氨酸蛋白酶-3，-8和9是否參與到這個過程。我的數據表明過氧化氫誘導細胞凋亡是通過內源和外源通路導致半胱氨酸酶-3激活，而TRPM2在這個過程中起到了重要的決定作用。總括而言，TRPM2 介導了過氧化氫誘導的內皮細胞凋亡，下調內源性的TRPM2的表達會保護血管內皮細胞。 / Reactive Oxygen Species (ROS) play a key role in normal physiological processes such as cell proliferation and growth, as well as in pathological processes. Under pathological conditions ROS contribute to vascular dysfunction and remodeling through oxidative damage. Oxidative stress is now thought to underlie many cardiovascular diseases. Accumulating evidence also demonstrate that many ROS-induced functional abnormalities in the cardiovascular system are preceded by an elevation of intracellular Ca²⁺. / In the first part, I compared the Ca²⁺ responses to ROS between mouse endothelial cells derived from large-sized artey aortas (aortic ECs), and small-sized mesenteric arteries (MAECs). Application of hydrogen peroxide (H₂O₂) caused an increase in cytosolic Ca²⁺ levels ([Ca²⁺]i) in both cell types. The [Ca²⁺]i rises diminished in the presence of U73122, a phospholipase C inhibitor, or Xestospongin C (XeC), an inhibitor for inositol-1,4,5-trisphosphate (IP₃) receptors. In addition, treatment of endothelial cells with H₂O₂ reduced the Ca²⁺ responses to subsequent challenge of ATP. The decreased Ca²⁺ responses to ATP were resulted from a pre-depletion of intracellular Ca²⁺ stores by H₂O₂. Interestingly, we also found that Ca²⁺ store depletion was more sensitive to H₂O₂ treatment in endothelial cells derived from mesenteric arteries than those of derived from aortas. Hypoxanthine-xanthine oxidase (HX-XO) was also found to induce [Ca²⁺]i rises in both types of endothelial cells, the effect of which was mediated by superoxide anions and H₂O₂ but not by hydroxyl radicals. H₂O₂ made a greater contribution to HX-XO-induced [Ca²⁺]i rises in endothelial cells from mesenteric arteries than those from aortas. In summary, H₂O₂ could induce store Ca²⁺ release via phospholipase C-IP₃ pathway in endothelial cells. Emptying of intracellular Ca²⁺ stores contributed to the reduced Ca²⁺ responses to subsequent ATP challenge. Furthermore, the Ca²⁺ responses in endothelial cells of small-sized arteries were more sensitive to H₂O₂ than those of large-sized arteries. / In the second part, I used murine heart microvessel endothelial cell line H5V as a model of endothelial cells from small-sized arteries to investigate the role of Melastatin-like transient receptor potential channel 2 (TRPM2) channels in H₂O₂-induced Ca²⁺ responses and apoptosis. TRPM2 is an oxidant-sensitive cationic non-selective channel that is expressed in mammalian vascular endothelium. A TRPM2 blocking antibody channel (TM2E3), which targets the E3 region near the ion permeation pore of TRPM2, was developed. Treatment of H5V cells with TM2E3 reduced the Ca²⁺ responses to H₂O₂. Suppressing TRPM2 expression using TRPM2-specific short hairpin RNA (shRNA) had similar inhibitory effect in H₂O₂-induced Ca²⁺ responses. H₂O₂-induced apoptotic cell death in H5V cells was examined using MTT assay, DNA ladder formation analysis, and DAPI-based nuclear DNA condensation assay. Based on these assays, TM2E3 and TRPM2-specific shRNA both showed protective effect on H₂O₂-induced apoptotic cell death. In contrast, overexpression of TRPM2 in H5V cells increased the Ca²⁺ responses to H₂O₂ and aggravated the apoptotic cell death in response to H₂O₂. These findings strongly suggest that the TRPM2 channel mediates Ca²⁺ overload in response to H₂O₂ and contributes to oxidant-induced apoptotic cell death in vascular endothelial cells. I also examined the downstream cascades of TRPM2 activation and explored whether caspase-3, -8 and -9 were involved in this process. My data indicates that H₂O₂-induced cell apoptosis through both intrinsic and extrinsic apoptotic pathways, leading to activation of caspases-3. Furthermore, TRPM2 played an essential role in the process. Together, my data suggest that TRPM2 mediates H₂O₂-induces endothelial cell death and that down-regulating endogenous TRPM2 could be a means to protect the vascular endothelial cells from apoptotic cell death. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Sun, Lei. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2012. / Includes bibliographical references (leaves 101-114). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract also in Chinese. / Declaration of Originality --- p.I / Abstract --- p.II / 論文摘要 --- p.IV / Acknowledgments --- p.VI / Abbreviations and Units --- p.VII / Table of Contents --- p.IX / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Reactive oxygen species and Reactive nitrogen species --- p.1 / Chapter 1.1.1 --- What is oxidative stress? --- p.1 / Chapter 1.1.2 --- Types of ROS --- p.2 / Chapter 1.1.2.1 --- Hydroxyl radical (*OH) --- p.2 / Chapter 1.1.2.2 --- Hydrogen peroxide (H₂O₂) --- p.3 / Chapter 1.1.2.3 --- Superoxide (O₂*⁻) --- p.4 / Chapter 1.1.2.4 --- Nitric oxide (NO) --- p.5 / Chapter 1.1.3 --- ROS-producing systems --- p.6 / Chapter 1.1.3.1 --- NAD(P)H oxidase --- p.6 / Chapter 1.1.3.2 --- Xanthine oxidase (XO) --- p.7 / Chapter 1.1.3.3 --- The mitochondrial respiratory chain --- p.8 / Chapter 1.1.3.4 --- Uncoupled endothelial NO synthase --- p.8 / Chapter 1.1.4 --- Antioxidant defense mechanisms in the cardiovascular systems --- p.9 / Chapter 1.1.4.1 --- SOD --- p.9 / Chapter 1.1.4.2 --- Catalase --- p.10 / Chapter 1.1.4.3 --- Glutathione peroxidase (GPx) --- p.10 / Chapter 1.1.4.4 --- Small molecules --- p.11 / Chapter 1.1.5 --- Role of oxidative stress in human diseases --- p.12 / Chapter 1.1.6 --- Endothelium dysfunction in oxidative stress-relating human diseases --- p.12 / Chapter 1.1.7 --- Role of Ca²⁺ in oxidative stress-relating human diseases --- p.14 / Chapter 1.1.8 --- Differential effects of ROS on endothelial calcium signaling --- p.15 / Chapter 1.1.8.1 --- Multiple Oxidative Stress-induced Ca²⁺ signaling pathway --- p.16 / Chapter 1.1.9 --- Effects of ROS on Agonist-induced endothelial calcium signaling --- p.19 / Chapter 1.1.10 --- Role of H₂O₂ as EDHF --- p.20 / Chapter 1.1.11 --- Differential effect of ROS on cells derived from large-sized and small-sized artries --- p.21 / Chapter 1.2 --- The transient receptor potential (TRP) Channels --- p.21 / Chapter 1.2.1 --- TRP Channel structure --- p.22 / Chapter 1.2.2 --- TRP Channel function --- p.23 / Chapter 1.2.3 --- TRPM subfamily --- p.23 / Chapter 1.2.3.1 --- TRPM2 Property and Structure --- p.24 / Chapter 1.2.3.2 --- TRPM2 Expression --- p.25 / Chapter 1.2.3.3 --- TRPM2 Activator --- p.25 / Chapter 1.2.3.4 --- TRPM2 Physiological and pathophysiological function --- p.28 / Chapter Chapter 2 --- Objectives of the Present Study --- p.35 / Chapter Chapter 3 --- Materials and methods --- p.37 / Chapter 3.1 --- Ethics statement --- p.37 / Chapter 3.2 --- Materials --- p.37 / Chapter 3.3 --- Methods --- p.38 / Chapter 3.3.1 --- Cell culture --- p.38 / Chapter 3.3.1.1 --- Primary Cell Culture --- p.38 / Chapter 3.3.1.2 --- H5V endothelial cell line --- p.39 / Chapter 3.3.1.3 --- Human embryonic kidney 293 (HEK293) cells --- p.39 / Chapter 3.3.4. --- TRPM2-specific shRNA, TRPM2 and transfection --- p.39 / Chapter 3.3.5 --- Western blotting --- p.40 / Chapter 3.3.6 --- [Ca²⁺]i Studies --- p.43 / Chapter 3.3.6.1 --- Fluo-4/AM- Measuring intracellular [Ca²⁺]i --- p.43 / Chapter 3.3.6.2 --- Fura-2/AM-Measuring intracellular [Ca²⁺]i --- p.44 / Chapter 3.3.6.3 --- Mag-fluo-4-Measuring Ca²⁺ Content in Intracellular Ca²⁺ Stores --- p.45 / Chapter 3.3.7 --- IP₃ measurement --- p.45 / Chapter 3.3.8 --- Electrophysiology --- p.46 / Chapter 3.3.9 --- TRPM2 blocking antibody (TM2E3) and Pre-immune IgG Generation --- p.46 / Chapter 3.3.10 --- DNA fragmentation assay --- p.47 / Chapter 3.3.11 --- DAPI Staining --- p.48 / Chapter 3.3.12 --- MTT assay --- p.48 / Chapter 3.3.13 --- Statistical analysis --- p.49 / Chapter Chapter 4 --- Effect of Hydrogen Peroxide and Superoxide Anions on Cytosolic Ca²⁺: Comparison of Endothelial Cells from Large-sized and Small-sized Arteries --- p.50 / Chapter 4.1 --- Introduction --- p.50 / Chapter 4.2 --- Materials and methods --- p.52 / Chapter 4.2.1 --- Primary Cell Culture --- p.52 / Chapter 4.2.2 --- [Ca²⁺]i Measurement --- p.52 / Chapter 4.2.3 --- Measuring Ca²⁺ Content in Intracellular Ca²⁺ Stores --- p.52 / Chapter 4.2.4 --- IP₃ measurement --- p.53 / Chapter 4.2.5 --- Data Analysis --- p.53 / Chapter 4.3 --- Results --- p.53 / Chapter 4.3.1 --- Both Ca²⁺ entry and store Ca²⁺ release contributed to H₂O₂-induced [Ca²⁺]i rises.. --- p.53 / Chapter 4.3.2 --- H₂O₂ enhanced IP₃ production and store Ca²⁺ release --- p.54 / Chapter 4.3.3 --- H₂O₂ reduced the Ca²⁺ responses to ATP in a H₂O₂ concentration and incubation time dependent manner --- p.54 / Chapter 4.3.4 --- H₂O₂ induced Ca²⁺ store depletion --- p.55 / Chapter 4.3.5 --- Ca²⁺ responses to ATP in the absence of H₂O₂ --- p.56 / Chapter 4.3.6 --- Non-involvement of hydroxyl radical --- p.56 / Chapter 4.3.7 --- HX-XO-induced [Ca²⁺]i rises were caused by superoxide anion and hydrogen peroxide --- p.56 / Chapter 4.4 --- Discussion --- p.68 / Chapter Chapter 5 --- Role of TRPM2 in H₂O₂-induced cell apoptosis in endothelial cells --- p.72 / Chapter 5.1 --- Introduction --- p.72 / Chapter 5.2 --- Materials and Methods --- p.73 / Chapter 5.2.1 --- Cell Culture --- p.74 / Chapter 5.2.2 --- [Ca²⁺]i measurement --- p.74 / Chapter 5.2.3 --- DNA fragmentation assay --- p.74 / Chapter 5.2.4 --- MTT assay --- p.74 / Chapter 5.2.5 --- TRPM2-specific shRNA, TRPM2 and transfection --- p.75 / Chapter 5.2.6 --- Electrophysiology --- p.75 / Chapter 5.2.7 --- Western blotting --- p.75 / Chapter 5.2.8 --- DAPI Staining --- p.76 / Chapter 5.2.9 --- Data analysis --- p.76 / Chapter 5.3 --- Results --- p.76 / Chapter 5.3.1 --- Involvement of TRPM2 channels in H₂O₂-induced Ca²⁺ influx in H5V cells --- p.76 / Chapter 5.3.2 --- Involvement of TRPM2 channels in H₂O₂-elicited whole-cell current change in H5V cells --- p.77 / Chapter 5.3.3 --- Role of TRPM2 channels in H₂O₂-induced apoptotic cell death in H5V cells --- p.78 / Chapter 5.3.4 --- Involvement of caspases in H₂O₂-induced apoptotic cell death --- p.79 / Chapter 5.3.5 --- Involvement of TRPM2 in TNF-α-induced cell death in H5V cells --- p.79 / Chapter 5.3 --- Discussion --- p.90 / Chapter Chapter 6 --- General Conclusions, Disscussion and Future work --- p.94 / Chapter 6.1 --- General Conclusions --- p.94 / Chapter 6.2 --- Discussion --- p.95 / Chapter 6.2.1. --- Comparative study --- p.95 / Chapter 6.2.2. --- IP₃ receptor (IP₃R) --- p.95 / Chapter 6.2.3. --- TM2E3-Specific blocking antibody of TRPM2 --- p.95 / Chapter 6.2.4. --- Pathological effect of H₂O₂ at high concentration --- p.96 / Chapter 6.2.5 --- Non-change on Basal [Ca²⁺]i --- p.97 / Chapter 6.3. --- Future work --- p.98 / References --- p.101

Made available in DSpace on 2017-07-24T19:22:17Z (GMT). No. of bitstreams: 1 Reila Mendes.pdf: 2640941 bytes, checksum: ae80dd043b80ca7c3792d907a25ab34f (MD5) Previous issue date: 2012-02-23 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / Periodontal disease is an inflammatory chronic disorder caused by a small group of gram-negatives bacteria witch colonizes the subgengival area. This disease is characterized by the destruction of the periodontal tissues, including bone resorption and loss of clinical attachment level. Observational studies have shown an increase in the risk of cardiovascular diseases, specially atherosclerosis and hypertension, among the subjects affected by the periodontal disease. The literature also reports endothelial dysfunction among these patients. Data suggest that the systemic inflammation due to the biofilm present in periodontits and the reduction in the nitric oxide availability may be, at least in part, the cause of endothelial dysfunction, which leads to cardiovascular disorders. An increase in vascular COX-2 expression has been demonstrated among diseases related to endothelial dysfunction. COX-2 expression seems to have an important protector function through the production of arachidonic acid metabolites with vasodilator and antitrombotic properties. Therefore, COX-2 inhibition may represent negative cardiovascular implications. The purpose of this research was to evaluate the effect of COX-2 inhibition on the vascular reactivity and on the heart tissue of animals with periodontitis. At day 0, Wistar rats were subdivided into the following groups: ligature + etoricoxib (the animals received ligatures and were treated with etoricoxib 10 mg/kg p.o., for seven days, from the day 14), ligature + vehicle (the animals were treated with distilled water), sham + etoricoxib (the animals went through a sham procedure: the ligatures were positioned and immediately removed) and sham + vehicle. The rats were prepared for the data collection and sacrificed at day 21. Changes on the vasoconstrictor response were not observed. However, the group ligature + etoricoxib showed a tendency to have the vasodilator response reduced. All the groups showed histological cardiac alterations, especially the groups that received etoricoxib, when submitted to ischemia with isoprenaline. It is suggested, though, that COX-2 inhibition in an experimental model of periodontal disease may increase cardiovascular disorders. / A periodontite é uma doença inflamatória crônica iniciada e perpetuada por bactérias anaeróbicas gram-negativas que colonizam a área subgengival. Esta doença é caracterizada pela destruição do tecido periodontal de inserção, reabsorção óssea, infiltração de leucócitos e formação de bolsa periodontal. Estudos observacionais têm mostrado um significativo aumento do risco de doenças cardiovasculares, principalmente aterosclerose e hipertensão, entre pessoas com periodontite. A literatura mostra também a presença de disfunção endotelial nesses pacientes. Os dados sugerem que a inflamação sistêmica induzida pela microbiota presente na doença periodontal e a diminuição na biodisponibilidade do óxido nítrico podem ser, pelo menos em parte, a causa da disfunção endotelial, que por sua vez leva a doenças cardiovasculares. Um aumento na expressão vascular da ciclooxigenase-2 (COX-2) tem sido consistentemente demonstrado em patologias que apresentam disfunção endotelial. A expressão da COX-2 nesta condição parece ter um importante papel protetor através da produção de metabólitos do ácido araquidônico com propriedades vasodilatadoras e antitrombóticas. Dessa maneira, a inibição da COX-2 pode apresentar aspectos cardiovasculares negativos. Assim, a proposta deste trabalho foi avaliar o efeito da inibição COX-2 sobre a reatividade vascular e sobre o tecido cardíaco de animais com periodontite. No dia 0, ratos Wistar foram subdivididos nos seguintes grupos: ligadura + etoricoxibe (receberam ligaduras e foram medicados com etoricoxibe 10 mg/kg v.o. por sete dias, a partir do dia 14), ligadura + veículo (receberam água destilada), falso-operado + etoricoxibe (passaram pelo procedimento de falsa-cirurgia, as ligaduras foram colocadas e imediatamente removidas) e falso-operado + veículo. Os animais foram preparados para aferição dos dados e sacrificados no dia 21. Não foram observadas alterações na resposta vasoconstritora, porém o grupo ligadura + etoricoxibe mostrou uma tendência em ter a resposta vasodilatadora reduzida. Quando submetidos à isquemia com isoprenalina, todos os grupos apresentaram alterações histológicas cardíacas, especialmente os que receberam etoricoxibe. Sugere-se, pois, que a inibição da COX-2 em um modelo experimental de periodontite exacerbe alterações cardiovasculares.

Leung, Pan Cheung Catherine. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2003. / Includes bibliographical references (leaves 105-120). / Abstracts in English and Chinese. / DECLARATION --- p.II / ACKNOWLEDGEMENTS --- p.III / ENGLISH ABSTRACT --- p.IV / CHINESE ABSTRACT --- p.VII / Chapter MODULE 1. --- INTRODUCTION --- p.1 / Chapter 1.1. --- Vascular Endothelium --- p.1 / Chapter 1.1.1. --- Vascular Endothelial Functions --- p.1 / Chapter 1.1.2. --- Calcium Signaling in Vascular Endothelial Cells --- p.2 / Chapter 1.2. --- The Founding Member of TRP Family: Drosophila TRP --- p.3 / Chapter 1.2.1. --- Discovery of Drosophila TRP and TRP-related Proteins --- p.3 / Chapter 1.2.2. --- Drosophila TRPs: Ca2+-permeable Channels? --- p.3 / Chapter 1.3. --- Mammalian TRP Superfamily --- p.5 / Chapter 1.3.1. --- The TRP Subfamily: TRPV --- p.9 / Chapter 1.3.2. --- The TRP Subfamily: TRPM --- p.9 / Chapter 1.3.3. --- The TRP Subfamily: TRPC --- p.11 / Chapter 1.4. --- Functional and Physiological Roles of Mammalian TRPCs --- p.12 / Chapter 1.4.1. --- TRPC1 --- p.15 / Chapter 1.4.2. --- TRPC2 --- p.16 / Chapter 1.4.3. --- "TRPC3, TRPC6 and TRPC7" --- p.17 / Chapter 1.4.4. --- TRPC4 and TRPC5 --- p.19 / Chapter 1.4.5. --- Over-expression of TRPCs: Physiologically Relevant Channels? --- p.20 / Chapter 1.4.6. --- Alternatives to Heterologous Expression Study --- p.21 / Chapter 1.5. --- Aims of the Study --- p.23 / Chapter MODULE 2. --- MATERIALS AND METHODS --- p.24 / Chapter 2.1. --- Functional Characterization of TRPCs by Antisense Technique --- p.24 / Chapter 2.1.1. --- Restriction Enzyme Digestion --- p.26 / Chapter 2.1.2. --- Purification of Released Inserts and Cut pcDNA3 Vectors --- p.27 / Chapter 2.1.3. --- "Ligation of TRPC Genes into Mammalian Vector, pcDNA3" --- p.27 / Chapter 2.1.4. --- Transformation for the Desired Clones --- p.28 / Chapter 2.1.5. --- Plasmid DNA Preparation for Transfection --- p.28 / Chapter 2.1.6. --- Confirmation of the Clones］ --- p.29 / Chapter 2.1.6.1. --- Restriction Enzymes Strategy --- p.29 / Chapter 2.1.6.2. --- Polymerase Chain Reaction (PRC) Check --- p.30 / Chapter 2.1.6.3. --- Automated Sequencing --- p.31 / Chapter 2.2. --- Establishing Stable Cell Lines --- p.33 / Chapter 2.2.1. --- Cell Culture --- p.33 / Chapter 2.2.2. --- Transfection Conditions Optimization --- p.33 / Chapter 2.2.3. --- Geneticin Selection --- p.35 / Chapter 2.3. --- Expression Pattern Studies of TRPC Genes in Vascular Tissues --- p.38 / Chapter 2.3.1. --- Immunofluorescence Staining in Cultured CPAE Cells --- p.38 / Chapter 2.3.2. --- Immunolocalization in Human Cerebral and Coronary Arteries --- p.40 / Chapter 2.3.2.1. --- Paraffin Section Preparation --- p.40 / Chapter 2.3.2.2. --- "Immunohistochemistry for TRPC1, 3, 4 and 6 Channels" --- p.40 / Chapter 2.3.2.3. --- Subcellular Localization of hTRPC1 and hTRPC3 Channels in Endothelial Cells --- p.42 / Chapter 2.4. --- Study of Bradykinin-induced Ca2+ Entry by Calcium Imaging --- p.47 / Chapter 2.4.1. --- Primary Aortic Endothelial Cell Culture --- p.47 / Chapter 2.4.2. --- Fura-2 Measurement of [Ca2+］］］ --- p.47 / Chapter 2.5. --- Study of Functional Role of TRPC6 in Stably Transfected H5V Cells … --- p.49 / Chapter 2.5.1. --- Protein Sample Preparation --- p.49 / Chapter 2.5.2. --- Western Blot Analysis --- p.50 / Chapter 2.5.3. --- Confocal Microscopy for Bradykinin-induced Calcium Entry --- p.51 / Chapter 2.6. --- Data Analysis --- p.52 / Chapter MODULE 3. --- RESULTS --- p.53 / Chapter 3.1. --- Bradykinin-induced Calcium Entry in Vascular Endothelial Cells --- p.53 / Chapter 3.1.1. --- Bradykinin-induced Calcium Entry --- p.53 / Chapter 3.1.2. --- Effects of cGMP and PKG on Bradykinin-induced Ca2+ Entry --- p.54 / Chapter 3.1.3. --- Effects of HOEUO on Bradykinin-induced Store-independent Ca2+ Entry --- p.55 / Chapter 3.1.4. --- Involvement of Phospholipase C Pathway in Bradykinin-induced Store-independent Ca2+ Entry --- p.55 / Chapter 3.2. --- Expression Pattern of TRPC Channels in Vascular Systems --- p.63 / Chapter 3.2.1. --- Immunolocalization of TRPC Homologues in CPAE Cells --- p.63 / Chapter 3.2.2. --- Immunolocalization of TRPC Homologues in Human Cerebral and Coronary Arteries --- p.66 / Chapter 3.2.3. --- Subcellular Localization of TRPC1 and TRPC3 Fused to Enhanced Green Fluorescence Protein (EGFP) --- p.77 / Chapter 3.3. --- Functional Role of TRPC6 Channels in Bradykinin-induced Calcium Entry --- p.81 / Chapter 3.3.1. --- Effect of Antisense TRPC6 Construct on Protein Expression --- p.81 / Chapter 3.3.2. --- Effect of Antisense TRPC6 on Bradykinin-induced Ca2+ Entry --- p.81 / Chapter 3.3.3. --- Effect of Antisense TRPC6 on Thapsigargin-depleted Ca2+ Stores --- p.82 / Chapter MODULE 4. --- DISCUSSION --- p.89 / Chapter 4.1. --- Characterization of Bradykinin-induced Ca2+ Entry in Endothelial Cells --- p.89 / Chapter 4.2. --- The Expression Pattern of TRPC Isoforms in Vascular Tissues --- p.93 / Chapter 4.3. --- Functional Characterization of TRPC6 Homologues in Bradykinin-induced Ca2+ Entry --- p.98 / Chapter 4.4. --- Perspectives --- p.103 / Chapter 4.5. --- Conclusion --- p.104 / Chapter MODULE 5. --- REFERENCES --- p.105

Cyclic nucleotide-gated (CNG) ion channels are Ca2+ permeable nonselective cation channels that are directly gated by binding of cAMP or cGMP, thus providing a linkage between two important signal molecules, cyclic nucleotides and calcium. They are known to play an important role in sensory transduction and in second-messenger modulation of synaptic neurotransmitter release. Previous studies showed that besides in neuronal cells, CNG were found also in non-neuronal tissues including heart, kidney, blood vessels and spleen, they are reported to be involved in a variety of cell function. / Ion channels play an indispensable role in endothelial cells, which is a unique signal-transducting surface in the vascular system that is responsible in altering vascular tone. The present study investigated the expression and functional roles of the cyclic nucleotide gated channels (CNG) in regulating the intracellular calcium level of vascular endothelial cells using molecular and calcium measurement techniques. / The present study provided evidence that the CNG channels, especially that of CNGA2, were expressed in vascular tissues. I used a variety of different methods, including RT-PCR, northern blot, in-situ hybridization, immunohistochemistry and western blot to study the localization of CNGA2 channels. RT-PCR amplify a CNGA2 fragment of 582bp from RNAs isolated from bovine vascular endothelial cell line, rat vascular smooth muscle cell line and rat aorta. Northern blot analysis detected a 2.3-kilobase (kb) CNGA2 transcript in rat aorta mRNA. The cellular distribution of CNGA2 was further studied by in-situ hybridization, which demonstrated expression of CNGA2 mRNA in human vascular endothelial and vascular smooth muscle cells. Immunohistochemistry data also agreed with those generated from in-situ hybridization. Western blot data also demonstrated proteins of CNG2 was expressed in both human vascular endothelial cells and vascular smooth cells layer. Subcellular localization of CNGA2 inside the vascular endothelial cells was also investigated with the use of a GFP linked CNGA2 channel gene. Taken together, the results showed that CNGA2 proteins were expressed on the plasma membrane of the vascular endothelial cells. (Abstract shortened by UMI.) / Cheng Kwong Tai Oscar. / "July 2005." / Adviser: Xiaoqiang Yao. / Source: Dissertation Abstracts International, Volume: 67-07, Section: B, page: 3531. / Thesis (Ph.D.)--Chinese University of Hong Kong, 2005. / Includes bibliographical references (p. 216-243). / Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Abstract in English and Chinese. / School code: 1307.

Yip Ham. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 132-141). / Abstracts in English and Chinese. / Acknowledgement --- p.i / Abbreviations --- p.ii / Abstract --- p.iii / 摘要 --- p.v / Chapter Chapter 1: --- Introduction --- p.5 / Chapter 1.1 --- Calcium Signaling --- p.5 / Chapter 1.1.1 --- Importance of Calcium to Life Forms --- p.5 / Chapter 1.1.2 --- Calcium Channels in Excitable and Non-excitable Cells --- p.6 / Chapter 1.2 --- Vascular Endothelial Cells --- p.8 / Chapter 1.2.1 --- General Functions --- p.8 / Chapter 1.2.2 --- Calcium signaling in Endothelial Cells --- p.9 / Chapter 1.3 --- Capacitative Calcium Entry (CCE) or Store-operated Calcium Entry (SOC) --- p.10 / Chapter 1.3.1 --- Definition --- p.10 / Chapter 1.3.2 --- Endoplasmic Reticulum (ER) as the Main Intracellular Calcium Stores --- p.10 / Chapter 1.3.3 --- Types of Experiments leading to the Identification of SOCs --- p.11 / Chapter 1.3.4 --- Emptying the Internal Calcium Store --- p.11 / Chapter 1.3.4.1 --- Inhibition of Calcium ATPase --- p.11 / Chapter 1.3.4.2 --- IP3 Triggered Release of Calcium --- p.12 / Chapter 1.3.5 --- "Store-operated Calcium Current, Icrac" --- p.15 / Chapter 1.3.6 --- Different Types of SOCs in Animal Cells --- p.16 / Chapter 1.4 --- Transient Receptor Potential (Trp) Gene & Transient Receptor Potential Like (Trpl) Gene in Drosophila --- p.17 / Chapter 1.4.1 --- Discoverery of Trp and Trpl --- p.17 / Chapter 1.4.2 --- Expression Studies of Drosophila Trp and Trpl --- p.19 / Chapter 1.4.2.1 --- Trp and Trpl form Channels but only Trp is Store Operated --- p.19 / Chapter 1.4.2.2 --- Co-expression Studies of Trp and Trpl --- p.20 / Chapter 1.5 --- Molecular Cloning and Expression of Mammalian Trp Homologues --- p.21 / Chapter 1.5.1 --- Seven Human Homologus of Trp were found --- p.21 / Chapter 1.5.2 --- Expression Pattern of mammalian Trp Homologues in Different Tissues --- p.23 / Chapter 1.5.3 --- Expression Studies of Mammalian Trp Homologues Yields Contradictory Results --- p.27 / Chapter 1.5.3.1 --- Trpl --- p.27 / Chapter 1.5.3.2 --- Trp2 --- p.28 / Chapter 1.5.3.3 --- Trp3 --- p.29 / Chapter 1.5.3.4 --- Trp4 --- p.30 / Chapter 1.5.3.5 --- Trp5 --- p.31 / Chapter 1.5.3.6 --- Trp6 --- p.31 / Chapter 1.5.3.7 --- Trp7 --- p.31 / Chapter 1.5.3.8 --- "Activation of Trp3, Trp6 and Trp7 by Diacylglycerol (DAG)" --- p.32 / Chapter 1.5.3.9 --- Functional Consequence after Co-expression of Trp Homologues --- p.34 / Chapter 1.5.3.10 --- Antisense Strategy to Determine the Functional Subunits of Store-operated Channels --- p.35 / Chapter 1.5.3.11 --- Possible Reasons for the Contradictory Results of Trp Homologues When Expressed in a Heterologous System --- p.36 / Chapter 1.6 --- Aims Of Study --- p.37 / Chapter Chapter 2. --- Materials and Methods --- p.38 / Chapter 2.1 --- Cell Culture --- p.38 / Chapter 2.2 --- Total RNA extraction from HCAEC 5286 --- p.39 / Chapter 2.3 --- Reverse Transcription from Cultured Human Coronary Artery Endothelial Cell Line HCAEC 5286 --- p.40 / Chapter 2.4 --- Polymerase Chain Reaction (PCR) of Partial Trp Gene Fragments --- p.41 / Chapter 2.5 --- Separation and Purification of PCR Products --- p.43 / Chapter 2.5.1 --- Separation --- p.43 / Chapter 2.5.2 --- Purification --- p.43 / Chapter 2.6 --- Confirmation of PCR Products --- p.44 / Chapter 2.7 --- Molecular Cloning of Trp Gene Family --- p.45 / Chapter 2.7.1 --- "Cloning of HTrpl, HTrp3, HTrp4,HTrp5,HTrp6, HTrp7" --- p.45 / Chapter 2.7.1.1 --- Polishing the Purified PCR Products --- p.47 / Chapter 2.7.1.2 --- Determination of the Amount of Polished PCR Products --- p.47 / Chapter 2.7.1.3 --- Inserting the PCR Products into the pPCR-Script Amp SK(+)Cloning Vector (Ligation) --- p.48 / Chapter 2.7.1.4 --- Transformation --- p.48 / Chapter 2.7.1.5 --- Preparing Glycerol Stocks Containing the Bacterial Clones --- p.49 / Chapter 2.7.1.6 --- Plasmid DNA Preparation --- p.49 / Chapter 2.8.1.7 --- Clones Confirmation --- p.50 / Chapter 2.8 --- In situ Hybridization --- p.54 / Chapter 2.8.1 --- Probe Preparation --- p.54 / Chapter 2.8.1.1 --- Trp1 Probe --- p.54 / Chapter 2.8.1.2 --- Trp3 Probe --- p.58 / Chapter 2.8.1.3 --- Trp4 Probe --- p.61 / Chapter 2.8.1.4 --- Trp5 Probe --- p.62 / Chapter 2.8.1.5 --- Trp6 Probe --- p.63 / Chapter 2.8.1.6 --- Trp7 Probe --- p.65 / Chapter 2.8.1.7 --- Control Probe --- p.66 / Chapter 2.8.2 --- Testing of DIG-Labeled RNA Probes --- p.66 / Chapter 2.8.3 --- Paraffin Sections Preparation --- p.67 / Chapter 2.8.4 --- In Situ Hybridization: Pretreatment --- p.67 / Chapter 2.8.5 --- "Pre-hybridization, Hybridization and Post-hybridization" --- p.68 / Chapter 2.8.5.1 --- Pre-Hybridization --- p.68 / Chapter 2.8.5.2 --- Hybridization --- p.68 / Chapter 2.8.5.3 --- Post-Hybridization --- p.69 / Chapter 2.8.6 --- Colorimetric Detection of Human Trps mRNA --- p.69 / Chapter 2.9 --- Northern Hybridization --- p.70 / Chapter 2.9.2 --- Labelling of Riboprobe with 32P --- p.70 / Chapter 2.9.3 --- Prehybridization and Hybridization with Radiolabeled RNA Probes --- p.73 / Chapter Chapter 3. --- Results --- p.74 / Chapter 3.1 --- Polymerase Chain Reaction (PCR) of Partial Trp Gene Fragments --- p.74 / Chapter 3.2.1 --- Expression of TRPs RNA in Human Coronary Artery --- p.78 / Chapter 3.2.1.1 --- Expression of Trp Transcripts in Tunica Intima and Media --- p.79 / Chapter 3.2.1.2 --- Expression of Trp Transcripts in the Tunica Adventitia --- p.88 / Chapter 3.2.2 --- Expression of TRPs RNA in Human Cerebral Artery --- p.97 / Chapter 3.2.2.1 --- Expression of Trp Transcripts in Tunica Intima and Media --- p.97 / Chapter 3.3 --- Northern Blot Analysis of Human Trp5 RNA in Human Multiple Tissue Blot --- p.115 / Chapter Chapter 4: --- Discussion --- p.117 / Chapter 4.1 --- Co-expression of Trps in Vascular Tissues --- p.117 / Chapter 4.1.1 --- Expression of Trps in Endothelia --- p.117 / Chapter 4.1.2 --- In Smooth Muscle Cells --- p.118 / Chapter 4.2 --- Trp Channel and Store-operated Channel in Endothelial Cells --- p.119 / Chapter 4.3 --- Heteromultimerization of Trps Subtypes --- p.120 / Chapter 4.4 --- Northern Blot Analysis --- p.124 / Chapter 4.5 --- Potential Physiological Functions of Trps --- p.125 / Chapter 4.6 --- Trp Channels as a Therapeutic Target? --- p.128 / Chapter 4.7 --- Technical Aspects in the Present Studies --- p.129 / Chapter 4.8 --- Conclusion --- p.131 / Reference --- p.133

Submitted by Suzana Dias (suzana.dias@famerp.br) on 2018-10-18T19:07:46Z No. of bitstreams: 1 LucianaNevesCosensoMatin_tese.pdf: 9100904 bytes, checksum: 8377e4f9c53810a2aa89b71e454e7aea (MD5) / Made available in DSpace on 2018-10-18T19:07:47Z (GMT). No. of bitstreams: 1 LucianaNevesCosensoMatin_tese.pdf: 9100904 bytes, checksum: 8377e4f9c53810a2aa89b71e454e7aea (MD5) Previous issue date: 2017-02-02 / Several trials have shown that dipeptidyl peptidase-4 (DPP-4) inhibitors, used to treat patients with diabetes mellitus type 2 (T2DM), improve endothelial function. Objectives: The current study investigated the effects of vildagliptin, a DPP-4 inhibitor, compared to glibenclamide on endothelial function and arterial stiffness (AS) in patients with T2DM and hypertension (HT). Casuistics and Methods: This trial was a prospective randomized, open label, controlled by drug. Fifty patients aged over 35 years with T2DM and hypertension, without cardiovascular disease, were randomly allocated to treatment with vildagliptin (n=25) or glibenclamide (n=25). Both groups used metformin. A 24-h non-invasive ambulatory blood pressure monitoring and assessment of endothelial function were performed before and after 12 weeks of treatment. Endothelial function was evaluated by peripheral artery tonometry (Endo- PAT 2000), measuring the reactive hyperemia index (RHI) and arterial stiffness. AS was also evaluated by augmentation index (Aix@75), pulse wave velocity (PWV) and central systolic blood pressure (cSBP) parameters with a portable compact digital BP recorder Mobil-O-Graph® 24-hour PWA monitor. The primary study outcome was change in the RHI after vildagliptin vs. glibenclamide treatment. Results: There were no changes in RHI in the vildalgliptin group (before 2.348 ± 0.5868; after 2.2408 ± 0.6019, P = 0.742) or in the glibenclamide group (before 2.3636 ± 0.5163; after 2.3375 ± 0.4996, P = 0.950) and no difference between groups (P = 0.5479). There was no difference between vildagliptin and glibenclamide treatment in AIx@75 PAT (P = 0.696), in 24-hs: cSBP (P = 0.274) and in PWV (P = 0.324). Conclusions: Vildagliptin in patients with T2DM and HT did not change endothelial function and AS during 12 weeks. Thus, this drug has a neutral effect on vascular function, providing its effectiveness for the treatment of patients with cardiovascular disease. / Vários estudos demonstraram que os inibidores da dipeptidyl peptidase-4 (DPP-4), usados no tratamento de pacientes portadores de diabetes mellitus do tipo 2 (DM 2), melhoraram a função endotelial. Objetivos: O presente estudo avaliou os efeitos da vildagliptina, um inibidor de DPP-4, comparado à glibenclamida (sulfonilureia), na função endotelial, na rigidez arterial e na pressão arterial de 24 horas de pacientes com DM 2 e hipertensão arterial (HA). Casuística e Métodos: Este foi um estudo prospectivo, randomizado, aberto, controlado por fármaco, que incluiu cinquenta pacientes com idade superior a 35 anos, com DM 2 e HA, livres de doença cardiovascular, randomizados para tratamento com vildagliptina ou glibenclamida. Metformina foi adicionada a todos os pacientes. A monitorização ambulatorial de pressão arterial de 24 horas e avaliação da função endotelial foram realizadas antes e após 12 semanas de tratamento. A função endotelial foi avaliada pela tonometria arterial periférica (Endo-PAT 2000), que calcula o índice de hiperemia reativa (IHR) e a rigidez arterial por meio do augmentation index (Aix@75). A rigidez arterial também foi avaliada por parâmetros do Aix@75, velocidade da onda de pulso (VOP) e pressão arterial sistólica central (PSc) por meio de monitorização ambulatorial de 24 horas usando Mobil-O-Graph® PWA. O desfecho primário foi variação do IHR após tratamento com vildalgiptina comparado ao tratamento com glibenclamida. Resultados: Não houve diferença no IHR no grupo da vildagliptina (antes 2,348 ± 0,5868; depois 2,2408 ± 0,6019, P = 0,742) ou no grupo da glibenclamida (antes 2,3636 ± 0,5163; depois 2,3375 ± 0,4996, P = 0,950) e entre os grupos (P = 0,5479). Similarmente, o tratamento com vildagliptina e glibenclamida não produziu efeitos no AIx@75 PAT (P = 0,696), na 24-hs: PSc (P = 0,274) e na VOP (P = 0,324). Conclusões: O tratamento durante 12 semanas com vildagliptina em pacientes portadores de DM 2 e HA não alterou a função endotelial e nem a rigidez arterial. Assim, este fármaco apresenta uma ação neutra na função vascular, confirmando sua segurança no tratamento de pacientes com doença cardiovascular.

Enquanto há inúmeros trabalhos evidenciando a participação do território arterial na fisiopatologia da Hipertensão Arterial Sistêmica (HAS), pouco ainda se conhece da real participação do território venoso nessa doença. Estudos prévios demonstraram menor complacência venosa até mesmo em pacientes hipertensos limítrofe, e esta alteração não pode ser explicada como sendo apenas conseqüente a alteração do sistema simpático. Acrescidos a estas alterações, foi demonstrada disfunção endotelial no território venoso em pacientes com fatores de risco cardiovascular, incluindo HAS. Entretanto, ainda existem poucas informações sobre a correlação da disfunção endotelial venosa e/ou da capacitância e complacência venosas e seu impacto funcional na HAS. Neste protocolo foram avaliados 27 indivíduos do Grupo Controle (GC) (idade de 36,8±9,2 anos, 13 homens, IMC de 24,6±4,6 Kg/m2) e 31 pacientes do Grupo Hipertenso (GH) (idade de 38,2±10,5 anos, 15 homens e IMC de 26,1±3,1 Kg/m2). Curvas de pressão arterial (PA) foram obtidas de forma não invasiva com o Finometer®, durante 10 minutos de repouso na posição supina (basal) e durante 10minutos em manobra de modulação de volume (Tilt test). Por meio da análise das curvas, foram calculadas variáveis hemodinâmicas [PA sistólica e diastólica (PAS e PAD), freqüência cardíaca (FC), débito cardíaco (DC), índice cardíaco (CI), índice de volume sistólico (SVI) e índice de resistência vascular periférica (PRI)], além de ser realizada a análise espectral da FC (VFC) e da PAS (VPA). A capacitância e complacência venosas do antebraço foram aferidas por meio da pletismografia e a função endotelial venosa pela técnica da veia dorsal da mão (DHV), ambas avaliadas somente no momento basal. Resultados: O padrão hemodinâmico: o GH comparado com o GC apresentou maior PAS e PAD no momento basal (p<0,05). Em resposta ao Tilt test, houve: aumento de FC (p<0,05), diminuição da PAS (p<0,05), do DC (p<0,05), do CI (p<0,05) e do SVI (p<0,05) em ambos os grupos, de semelhante intensidade. Na avaliação da VFC no basal, não se detectou diferença entre os grupos com relação à FC, aos componentes normalizados da VFC (%LF, %HF) e na relação LF/HF (modulação autonômica). Em resposta ao Tilt test, em ambos os Grupos, houve aumento da FC (p<0,05) e da %LF (p<0,05), e queda da %HF (p<0,05), porém o GC apresentou respostas mais exacerbadas comparadas as do GH. Na avaliação da variabilidade da pressão arterial (VPA), observamos que todos os parâmetros foram semelhantes entre os grupos, tanto no basal quanto em reposta ao Tilt test, o mesmo ocorrendo na avaliação da sensibilidade do barorreflexo (ALFA LF). Com relação à capacitância venosa, o GH apresentou uma redução significativa (p<0,05) comparada ao GC nas pressões de oclusão de 30 e 40mmHg [4,8 (3,8-5,7) - 3,6 (2,8-4,6) vs 5,5 (4,8-7,3) - 4,7 (3,8-6,4), respectivamente]. A complacência venosa foi menor no GH. Considerando a função endotelial venosa, detectou-se uma menor venodilatação máxima em resposta a acetilcolina no GH [62,9 (38,3 79,9) vs 81,7 (65,3 99,1)], e similar venodilatação em resposta ao nitroprussiato de sódio, indicando a presença de disfunção endotelial venosa neste Grupo. Não foi possível evidenciar correlações entre diferentes parâmetros: complacência venosa e função endotelial venosa, DC, RVP e componente LF da PAS e nem entre função endotelial venosa com DC e RVP. Pode-se concluir que, na população de hipertensos estudada, há uma coexistência entre disfunção endotelial venosa e menor complacência venosa, porém não se evidenciaram correlações significativas entre estas variáveis, com os métodos utilizados no presente estudo / While there are numerous studies showing the involvement of the arteries in the pathophysiology of systemic arterial hypertension (AH), less is known about the role of the venous system in this disease. Previous studies have demonstrated lower venous compliance in established and borderline hypertensive patients, and this change can not be explained only by an increase in sympathetic activity. It is hypothesized that a lower venous compliance may have an impact on cardiac filling pressures and consequently on blood pressure levels. Furthermore, venous endothelial dysfunction, characterized by a decrease in venous dilation, was detected in patients with AH and with other cardiovascular risk factors. Therefore, we aimed to establish a correlation between venous endothelial dysfunction with venous compliance, and with venous compliance with different hemodynamic parameters. Casuistic and Methods: a total of 31 patients with stage 1 and 2 of AH (HG) (age of 38.2 ± 10.5 years, 15 men and BMI of 26.1 ± 3.1 kg/m2) and 27 normotensive subjects the control group (CG) (age 36.8 ± 9.2 years, 13 men, BMI 24.6 ± 4.6 kg/m2) were evaluated. Curves of blood pressure (BP) were obtained non-invasively with Finometer ® device, and were recorded for 10-minute in both supine (baseline) position and during tilt test maneuver. By analyzing the curves, hemodynamic variables [systolic and diastolic BP (SBP and DBP), heart rate (HR), cardiac output (CO), cardiac index (CI), stroke volume index (SVI) and index vascular resistance (IVS)], and spectral analysis of HR (HRV) and SBP (BPV) were performed. The venous capacitance and compliance of the forearm were measured by plethysmography and venous endothelial function by the technique of dorsal hand vein (DHV), both assessed only at baseline. Results: At baseline, the HG showed a different hemodynamic pattern compared to the CG, with higher SBP and DBP. In response to the tilt test, both groups presented a similar response: an increase in HR (p<0.05) and a decrease in SBP, CO, IC, and of SVI (p<0.05). In the assessment of HRV at baseline, there was no difference between groups for HR, %LF, %HF and LF/HF ratio. In response to Tilt test in both groups both groups showed an increase in HR (p<0.05) and LF% (p<0.05), and a decrease in HF% (p<0.05), but the CG had higher changes compared to HG. All parameters of blood pressure variability and baroreflex sensitivity (ALFA LF) were similar between groups. HG showed a significant reduction (p<0.05) in venous capacitance compared to GC at occlusion pressures of 30 and 40 mmHg [4.8 (3.8 to 5.7) - 3.6 (2, 8 to 4.6) vs 5.5 (4.8 to 7.3) - 4.7 (3.8 to 6.4), respectively]. Venous compliance was lower in HG, and also the venous endothelial function. It was possible to detect a smaller venodilation response to acetylcholine in the HC [62.9 (38.3 to 79.9) vs 81.7 (65.3 to 99.1)], and similar venodilation in response to sodium nitroprusside, indicating the presence of venous endothelial dysfunction in this group. There were no significant correlations between venous endothelial dysfunction with venous compliance, and with venous compliance with different hemodynamic parameters and autonomic parameters. In conclusion, in the hypertensive population studied it was demonstrated the coexistence of venous endothelial dysfunction and reduced venous compliance, but it was not possible to detect significant correlations between those variables with the methods used in the present study

Nosso objetivo foi verificar a participação do TLR4 na pressão arterial e reatividade vascular em ratos SHR. O TLR4 está mais expresso em artérias mesentéricas de resistência de SHR com 15 semanas do que em Wistar com 15 e SHR com 5 semanas. SHR e Wistar com 15 semanas foram tratados com anti-TLR4 (1mg/dia) ou IgG (controle) por 15 dias via i.p. A expressão do TLR4, MyD88, a fosforilação da P38 e NF-kB p65, e a secreção de IL-6 foi menor nos SHR anti-TLR4 do que nos SHR IgG. Os SHR tratados com anti-TLR4 apresentaram redução na pressão arterial versus SHR IgG. A resposta máxima ao KCl e à noradrenalina (NA) foram normalizadas após o uso do anti-TLR4 no SHR, por vias dependentes de COX-1, COX-2 e do NF-kB. O uso do L-NAME diminuiu a resposta contrátil à NA no SHR IgG sendo que o anti-TLR4 melhorou essa resposta em SHR. O anti-TLR4 aumentou a expressão da eNOS e preveniu a geração de espécies reativas de oxigênio em SHR. Sugerimos que o TLR4 está associado com o aumento da pressão arterial e com a disfunção vascular presente na hipertensão arterial. / Our objective was to investigate the role of TLR4 in blood pressure and vascular reactivity in SHR. TLR4 is more expressed in mesenteric resistance arteries from SHR 15 week than in Wistar with 15 and SHR 5 weeks. Wistar and SHR with 15 weeks were treated with anti-TLR4 (1mg/dia) or IgG (control) for 15 days via ip. The expression of TLR4, MyD88, phosphorylation of p38 and NF-kB p65, and IL-6 secretion was lower in SHR TLR4 than in SHR IgG. SHR treated with anti-TLR4 had reduced blood pressure versus SHR IgG. The maximal response to KCl and noradrenaline (NA) were normalized after anti-TLR4 treatment in SHR by mechanisms dependent on COX-1, COX-2 and NF-kB. The use of L-NAME decreased the contractile response to NA in SHR IgG and anti-TLR4 improved this response in SHR. The anti-TLR4 increased eNOS expression and prevented the generation of reactive oxygen species in SHR. We suggest that the TLR4 is associated with increased blood pressure and vascular dysfunction in hypertension.