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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
41

Functional study of amylin and regulation of amylin receptor

Huang, Xiaofang January 2010 (has links)
Amylin, a 37 amino acid peptide secreted from pancreatic beta cells upon stimulation by meal/glucose, belongs to the family of the calcitonin or calcitonin gene-related peptide (CGRP) and shares up to 50% homology with CGRP, which is a well-documented pain-related peptide. The amylin receptor is composed of a calcitonin receptor (CTR) and receptor activity modifying proteins (RAMPs). Numerous studies have shown that amylin plays an important role in glucose homeostasis and food intake. Few studies have been conducted with respect to the effect of amylin in the central or peripheral neuraxis. In this thesis, immunohistochemical study revealed a dense network of amylin-immunoreactive (irAMY) cell processes in the superficial dorsal horn of the mice. Numerous dorsal root ganglion and trigeminal ganglion cells expressed moderate to strong irAMY. Reverse transcriptase-polymerase chain reaction (RT-PCR) revealed amylin receptor mRNA in the mouse spinal cord, brain stem, cortex, hypothalamus and hippocampus. The nociceptive or antinociceptive effects of amylin were evaluated in the tail flick and acetic acid-induced writhing test. Amylin (1-10 µg, i.t.) reduced the number of writhing in a dose-dependent manner. Pretreatment of the mice with the amylin receptor antagonist salmon calcitonin (8-32) [sCT(8-32)]or AC187 by i.t. antagonized the effect of amylin on acetic acid-induced writhing test. Locomotor activity was not significantly modified by amylin injected either i.p. (0.01-1 mg/kg) or i.t. (1-10 µg). Measurement of c-fos mRNA by RT-PCR or proteins by Western blot showed that the levels were up-regulated in the spinal cord of mice in acetic acid-induced visceral pain model and the increase was attenuated by pretreatment with amylin. Pretreatment of sCT[8-32] or AC187 significantly reversed the effect of amylin on c-fos expression in the spinal cord. As the neuronal response to amylin is closely dependent on the molecular property of amylin receptor, the localization, internalization and regulation of the calcitonin and amylin receptor were examined in the second part of the thesis. Immunofluorescence microscopy demonstrated the surface expression of CTRa, and intracellular distribution of RAMP1. Moreover, co-expression of CTRa translocated the RAMP1 to the cell surface and generated the amylin receptor phenotype. Both immunocytochemistry and on cell western analysis showed the internalization of CTRa and amylin receptor (CTRa/RAMP1) stimulated by different agonists, which was partially ß-arrestin dependent. Moreover, RAMP1 did not change the surface expression pattern of CTRa, but co-localized with the receptor with and without agonist treatment. sCT and amylin activated the ERK1/2 in HEK293 cells stably expressing amylin receptors, indicating the involvement of MAPK in amylin receptor signaling cascade. Collectively, these results led us to conclude that 1) irAMY is expressed in dorsal root ganglion neurons with their cell processes projecting to the superficial layers of the dorsal horn, and that the peptide by interacting with amylin receptors in the spinal cord may be antinociceptive; 2) RAMP1 does not change the pattern of CTR cell-surface localization and internalization, but receptor phenotype, presumably through a direct or indirect effect on the ligand-binding site; 3) amylin internalizes the amylin receptor (CTRa/RAMP1 complex); which is partially ß-arrestin dependent. Our studies extend the current knowledge of amylin on the spinal cord and new insight on the cellular and molecular mechanism underlying the antinociceptive effect of amylin. Also we demonstrate for the first time agonist induced-internalization of CTR/RAMP complex and its possible regulation pathway. / Pharmacology
42

Serum calcitonin gene-related peptide concentrations in the horse and their relationship to the Systemic Inflammatory response

Mitchell, Emma 24 October 2006 (has links)
Systemic inflammation is a leading cause of mortality and morbidity in both human and equine intensive care patients. This systemic inflammatory response may be due to insult from bacterial, viral, fungal or parasitic invasion or from trauma or hypoxemia. Local and systemic release of a wide variety of endogenous pro-inflammatory mediators results in activation of the innate immune system in order to resolve the insult. In sepsis this initial appropriate host response becomes amplified and deregulated leading to refractory hypotension and multiple organ dysfunction. The exact incidence of sepsis (SIRS due to bacterial infection) has not been reported in the equine literature (Roy 2004). Since early recognition and treatment of sepsis are associated with improved outcome the search for markers to accurately predict presence of sepsis and likelihood of survival continues. The serum concentration of both procalcitonin and its related molecule CGRP have been documented to increase in humans with SIRS, yet no literature exists as to the production or role of CGRP in equine patients with SIRS. This study showed that equine CGRP was produced in detectable quantities by healthy adult horses and neonatal foals less than two weeks of age using a rat á-CGRP ELISA. The low percentage recovery of CGRP from samples and the high lower limit of detection for the assay prevented establishment of a normal concentration range of CGRP in healthy horses. In both adult horses and foals with documented SIRS, CGRP concentrations were significantly increased at time of presentation to the hospital (p<0.0002, p<0.003 respectively). A trend towards increased serum CGRP concentration was present in anaesethized horses exposed to endotoxin, but this was not statistically significant (p< 0.067). / Master of Science
43

Osteogenic effect of magnesium and its potential application for fracture healing enhancement in ovariectomized rats.

January 2015 (has links)
我们的研究是基于发现镁金属的成骨现象。在我们组之前的工作中,我们发现大鼠股骨骨髓腔内植入镁棒后,在很短时间内(一周后)就会在股骨骨膜下部位形成新骨。这种镁导致的成骨现象是怎样发生的,以及我们能否利用镁金属的这种特性去促进骨质疏松骨折的愈合?对这两个问题的解答便构成了本篇论文的主要内容。 / 因为镁诱导的新生骨产生在骨膜下方,并且植入镁棒产生的成骨现象在骨膜剥除的部位消失,所以我们认为骨膜是镁成骨的关键点。骨膜是富含感觉神经纤维和干细胞的组织,而且动物骨的感觉神经分布主要集中在骨膜(约占总的神经数量的99%以上)。骨膜神经末端不仅仅感知痛觉触觉和温度觉,而且在外界刺激下释放感觉神经递质。神经递质包裹于处于神经末梢的囊泡当中,CGRP 是经典的也是分布最广的感觉神经递质。在动物体内,血液中CGRP 的含量随年龄的增加而减少,同时骨内的镁含量也随之流失。这也是老年龄动物骨折愈合较慢的原因之一。所以我们提出本课题的研究假设:镁金属降解产生的镁离子作用于骨膜部位的感觉神经末梢,刺激神经递质CGRP 的释放。骨膜内增多的CGRP 作用于骨膜内的干细胞进行成骨分化,最后形成新骨。我们进一步检测镁的这种成骨作用能否促进骨质疏松鼠骨折的愈合。 / 首先我们用过量的辣椒素破坏大鼠股骨的感觉神经末端之后,镁的成骨显著减少,这说明镁的成骨作用相当程度上依赖于通过骨膜的神经组织。我们通过免疫组化染色及蛋白定量测定发现,植入镁后的骨组织内CGRP(降钙素基因相关肽,一种感觉神经末端分泌的主要神经递质)含量增加了一倍多。我们用CGRP 受体拮抗剂同样发现可以部分抑制镁的成骨作用。我们推测镁降解过程中产生的镁离子在骨膜部位增加了感觉神经递质的释放,骨膜部位增多的神经递质作用于骨膜源性间充质干细胞以及骨髓源性间充质干细胞想成骨方向分化成骨。体外试验结果表明,CGRP 在高浓度下显著促进骨膜及骨髓源性干细胞的成骨分化。我们从大鼠的脊髓腰段L3-5 背根神经节分离出背根神经节神经元,在体外用荧光对神经元内的突触小泡进行染色,发现当培养液中的镁离子浓度升高时(1-2mM),这些富含神经递质CGRP 的突触小泡不但数目增加,而且从胞体中心向轴突末梢迁移。在这个过程中,我们同时记录到显著的镁离子内流。实验结果表明,镁离子可以促进神经元的复极化以及神经递质向轴突末端迁移聚集,从而在下一次刺激中释放出更多的神经递质。同时体外干细胞分化实验结果表明高浓度的镁离子(5-10mM)显著促进干细胞的成骨分化。对干细胞和神经元的胞内镁离子内流检测发现,在胞外镁离子浓度升高的情况下,胞内镁离子内流主要通过一种膜通道MagT1。至此,关于镁成骨的机制可以归纳为:镁金属在降解过程中产生的镁离子作用于骨膜感觉神经末梢,使之释放出更多的神经递质,增加释放的神经递质和镁离子共同促进分布在骨膜和骨髓的干细胞进行成骨分化,从而增加成骨。 / 镁的成骨效应使之有很大的潜力用于骨质疏松骨折的修复。由于镁金属强度不足以直接用来固定大鼠骨折,所以我们设计了一种中空的不锈钢针管作为髓内骨折固定针。针管中部与骨折线对应的部位开出一些小孔,细的镁棒可以插入针管,在体内镁降解产生的镁离子可以从中部的小孔释放出去发挥其成骨效应,进而促进骨折的愈合。我们用卵巢切除大鼠进行闭合性骨折造模,然后用我们设计的髓内针固定。X 射线结果表明,手术后第二、四周镁治疗组骨折愈合组织的面积和宽度显著大于对照组。Micro-CT 扫描结果也同样表明,镁治疗组骨折部位愈合组织的总体积和骨组织体积在术后第四周显著大于对照组。组织学染色表明,在术后第二周,镁治疗组的骨折部位的骨膜内成骨大量增加,并且有大量间充质细胞充塞与骨折部位。第术后第四周,更多的软骨组织形成于镁治疗组的骨折部位。荧光双染色结果也表明,镁治疗组的骨折部位在第四周有更多的新生骨形成。第八周和十二周的偏振光图像表明,镁治疗组的骨折愈合部位形成的胶原纤维比对照组更规则且更多更亮。这说明在骨折愈合后期软骨内成骨以及编制骨向层状骨转化的过程中,镁治疗组的骨重建更加规则。最后在第十二周的力学实验结果证明,镁治疗组的骨干所能承受的最大压力显著高于对照组(大约增强了27%)。这部分体内试验证明镁金属可以加速并优化大鼠骨质疏松骨折的愈合,而且我们设计的中空含镁髓内针可以作为将来临床新型骨折髓内固定针的原型。 / 结论:我们对镁成骨的作用和其机制进行了比较深入全面的研究,并初步证实镁金属可以用于动物骨质疏松骨折的修复。我们的研究结果为将来镁金属在临床尤其是骨科领域的实际应用提供了一些基本的理论依据。 / In the rodent femur, almost 99% of all sensory nerves are distributed densely in the periosteum. Neuropeptides encapsulated in the synaptic vesicles are located at the axon terminals and released through exocytosis after being stimulated at the sensory nerve endings. The neuropeptides released from nerve endings have an osteo-anabolic effect on osteoblasts. Among the many kinds of neuropeptides, which include α-calcitonin gene-related peptide (CGRP), substance P, and other amino molecules, CGRP is the classical and dominantly distributed peptide in sensory nerve endings. In aged animals, decreased serum CGRP and loss of bone Mg content may be the factors inhibiting fracture healing. / In this study, Mg was found to significantly promote new bone formation in the subperiosteal cortical region after it was intramedullarily implanted in the rat femur canal. Histomorphological analysis revealed that the newly formed bone grew from periosteum, a fibrous membrane constituted of blood vessels, sensory serves, and mesenchymal stem cells, and did not form any cartilage-like tissue, the latter of which is a feature of intramembranous ossification. Observation that Mg-induced new bone formation disappeared at the periosteum-stripped region revealed the existence of an interaction between the periosteum and Mg ions. / Based on previous findings, this study examined the following hypotheses: (1) Mg ions from Mg implanted in the rat femur canal act on sensory nerve endings in the periosteum and promote neuropeptide CGRP release, (2) mass CGRP release in the periosteum promotes periosteum-derived stem cells osteoblastogenesis and leads to new bone formation. Mg ions affect synaptic replasticity in dorsal root ganglia neurons, and (3) pure Mg metal affects fracture healing in ovariectomized (OVX) rats. / Neuropeptide CGRP plays a pivotal role in Mg-induced new bone formation. This hypothesis was supported by femur bone analysis showing that CGRP content significantly increased in Mg-implanted femur bone compared to control femur bone. When rat sensory nerves were destroyed by administration of high-dose capsaicin, induction of new bone formation by Mg implantation significantly decreased, proving that sensory nerves play an important role in Mg-induced osteogenesis. Because neuropeptide CGRP from sensory nerve endings may play a pivotal role in Mg’s osteogenic process, the effective CGRP antagonist BIBN4096bs was administered to Mg-implanted rats. Administration of the CGRP antagonist significantly reduced newly formed bone volume after Mg implantation. To examine whether this phenomenon is dependent on the interaction between neuropeptides and MSCs, which are richly distributed in the periosteum, periosteum-derived stem cells (PDSCs) and bone marrow-derived mesenchymal stem cells (BMSCs) were isolated from the periosteum and bone marrow, respectively. It was observed that high concentrations of CGRP significantly promoted osteogenic differentiation in both PDSCs and BMSCs while high concentrations of CGRP had an obvious chemotaxis effect on BMSCs. / Mg increases CGRP release by affecting DRG neurons. The results of immunochemical staining and ELISA CGRP quantification analysis of femur samples showed that femur CGRP content in Mg-implanted samples was almost twice that of controls. Previous studies reported that Mg ions could promote neural synaptic replasticity in hippocampus neurons in vitro. This study examined the hypothesis that Mg ions could promote synaptic replasticity in DRG neurons. The neural synaptic vesicles, which contain neuropeptides of DRG neurons, including CGRP, derived from the L3-5 dorsal root ganglion were stained in vitro. The synaptic vesicles were found to significantly increase in number when their medium was changed from Mg-free medium to Mg-rich medium of 1 mM and 2 mM and to migrate from the neuron body to its axon terminals. These results proved that Mg could facilitate neuron replasticity and prompt synaptic vesicle aggregation at axon terminals, indicating that much neuropeptide release occurs after stimulation. Real-time recording of the intracellular Mg signal revealed that DRG neuron Mg influx significantly increased after Mg medium had been added and that Mg influx into neurons was mainly through the membrane Mg ion channel MagT1. Implantation of Mg ions (MgCl₂) of high concentration was found to promote stem cell (PDSCs and BMSCs) osteogenic differentiation. Although the mechanism of Mg’s osteogenic effect on stem cells was not thoroughly studied, cellular Mg influx was found to increase in high-Mg medium through the membrane ion channel MagT1. / Mg accelerated bone fracture in ovariectomized rats. Mg metal is too soft to repair bone fracture in animal models. To overcome this challenge, we designed a novel intramedullary nail containing Mg to accelerate osteoporotic bone fracture healing in ovariectomized (OVX) rats. The novel nail is a hollow stainless steel needle with several interlacing arranged holes drilled midway through the needle. The Mg pin is inserted into the needle canal and Mg ions released through the holes on the needle reach the fracture line during degradation in vivo. Our findings indicate that use of this Mg-containing intramedullary nail could accelerate bone fracture healing in OVX rats. Review of post-surgery X-ray results showed that the fracture callus of the Mg-treated group was significantly larger than that of the control group at weeks 2 and 4. Review of micro-computed tomography (micro-CT) scanning images indicated that both the total volume and area of callus bone in the Mg-treated group exceeded those of the control group at week 4. However, no significant difference was found between the two groups regarding callus area and volume at week 12. / Histomorphological analysis showed a wider intramembranous ossification area and woven bone area in the Mg-treated group at weeks 2 and 4 and more cartilage tissue at the callus site in the Mg-treated group at week 4. Double fluorescence labeling staining revealed more densely stained newly formed bone in the Mg-treated group than the control group at week 4, indicating accelerated callus bone formation in the Mg-treated group. The callus was observed to be undergoing endochondral ossification and woven bone remodeling at weeks 8 and 12. Review of polarized light images showed brighter and more regularly arranged collagen fibers in the Mg-treated group compared to the control group. Biomechanical testing at week 12 revealed that the ultimate load of shaft bone in the Mg-treated group had increased 30% more than that of the control group. These results indicate that the novel Mg-containing intramedullary nail designed in this study could significantly accelerate and optimize osteoporotic fracture healing in OVX rat model. / Significance: The results of this study contribute to a thorough understanding of the osteogenic effect of Mg by explicating its bioeffect on neurons and stem cells. The novel Mg-containing intramedullary nail designed in this study appears promising in osteoporotic fracture healing and to have many potential clinical applications. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Detailed summary in vernacular field only. / Zhang, Yifeng. / Thesis (Ph.D.) Chinese University of Hong Kong, 2015. / Includes bibliographical references (leaves 170-180). / Abstracts also in Chinese.
44

Release and effects of calcitonin gene-related peptide in myocardial ischaemia /

Källner, Göran, January 1900 (has links)
Diss. (sammanfattning) Stockholm : Karol. inst. / Härtill 7 uppsatser.
45

Adrenomedullin, calcitonin gene-related peptide and endothelin-3 in mouse astrocyte cultures: actions and interactions.

January 2000 (has links)
by Chi Fung Yeung. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2000. / Includes bibliographical references (leaves 83-120). / Abstracts in English and Chinese. / abstract --- p.1 / table of contents --- p.3 / acknowledgments --- p.8 / declaration --- p.9 / list of figures and tables --- p.10 / list of abbreviations --- p.13 / Chapter chapter 1- --- general introduction --- p.15 / Chapter 1.1 --- VASOACTIVE PEPTIDES --- p.18 / Chapter 1.1.1 --- HISTORICAL BACKGROUND --- p.18 / Chapter 1.1.1.1 --- Adrenomedullin --- p.20 / Chapter 1.1.1.2 --- Calcitonin gene-related peptide --- p.21 / Chapter 1.1.1.3 --- Endothelin-3 --- p.22 / Chapter 1.1.2 --- "SYNTHESIS AND RELEASE OF ADRENOMEDULLIN, CALCITONIN GENE RELATED PEPTIDE AND ENDOTHELINS" / Chapter 1.1.2.1 --- SYNTHESIS AND RELEASE OF Adrenomeduulin --- p.24 / Chapter 1.1.2.2 --- SYNTHESIS AND RELEASE OF calcitonin gene related peptide --- p.25 / Chapter 1.1.2.3 --- SYNTHESIS AND RELEASE OF ENDOTHELINS --- p.25 / Chapter 1.1.3 --- "ADRENOMEDULLIN, CALCITONIN GENE RELATED PEPTIDE AND ENDOTHELINS IN THE CNS" --- p.26 / Chapter 1.1.4 --- "RECEPTORS OF ADRENOMEDULLIN, CALCITONIN GENE RELATED PEPTIDE AND ENDOTHELINS AND SIGNAL TRANSDUCTION" --- p.27 / Chapter 1.1.5 --- "BIOLOGICAL ACTIONS OF ADRENOMEDULLIN, CALCITONIN GENE RELATED PEPTIDE AND ENDOTHELINS" / Chapter 1.1.5.1 --- BIOLOGICAL ACTIONS OF ADRENOMEDULLIN --- p.30 / Chapter 1.1.5.1.1 --- haemodynamic effects of adrenomedullin --- p.30 / Chapter 1.1.5.1.2 --- Renal effects of Adrenomedullin --- p.31 / Chapter 1.1.5.1.3 --- Endocrine effects of Adrenomedullin --- p.31 / Chapter 1.1.5.1.4 --- Central effects of Adrenomedullin --- p.32 / Chapter 1.1.5.2 --- CALCITONIN GENE RELATED PEPTIDE / Chapter 1.1.5.2.1 --- haemodynamic effects of calcitonin gene related peptide --- p.33 / Chapter 1.1.5.2.2 --- Renal effects of calcitonin gene related peptide --- p.34 / Chapter 1.1.5.2.3 --- Endocrine effects of calcitonin gene related peptide --- p.34 / Chapter 1.1.5.2.4 --- Central effects of calcitonin gene related peptide --- p.35 / Chapter 1.1.5.3 --- ENDOTHELINS / Chapter 1.1.5.3.1 --- haemodyamic effects of endothelins --- p.36 / Chapter 1.1.5.3.2 --- Renal effects of Endothelins --- p.36 / Chapter 1.1.5.3.3 --- endocrine effects of endothelins --- p.37 / Chapter 1.1.5.3.4 --- Central effects of Endothelins --- p.37 / Chapter 1.1.6. --- PROLIFERATIVE OR ANTI-PROLIFERATIVE EFFECTS --- p.38 / Chapter 1.1.7 --- CLINICAL RELEVANCE OF VASOACTIVE PEPTIDES / Chapter 1.1.7.1 --- Clinical relevance of Adrenomedullin --- p.39 / Chapter 1.1.7.2 --- Clinical relevance of calcitonin gene related peptide --- p.40 / Chapter 1.1.7.3 --- Clinical relevance of Endothelins --- p.41 / Chapter 1.2 --- ASTROCYTES / Chapter 1.2.1 --- Historical background and astrocyte morphology --- p.42 / Chapter 1.2.2 --- Physiological roles of astrocytes --- p.44 / Chapter 1.2.3 --- Pathology of astrocytes --- p.45 / Chapter 1.3 --- NEUROPEPTIDE RECEPTORS AND ASTROCYTES / Chapter 1.3.1 --- Neuropeptide receptors on astrocytes --- p.47 / Chapter 1.3.2 --- Consequences of receptor activation --- p.49 / Chapter 1.4 --- AIMS OF THE THESIS --- p.50 / Chapter CHAPTER 2 --- "GENERAL MATERIALS AND METHODS, AND DATA ANALYSIS" / Chapter 2.1 --- MATERIALS / Chapter 2.1.1 --- ANIMALS --- p.54 / Chapter 2.1.2 --- PEPTIDE HORMONES --- p.54 / Chapter 2.1.3 --- ISOTOPES AND RADIOIMMUNOASSAY KITS --- p.54 / Chapter 2.1.4 --- CULTURE MATERIALS AND CHEMICALS --- p.55 / Chapter 2.1.5 --- PREPARATION OF MATERIALS / Chapter 2.1.5.1 --- Preparation of primary cultures of astrocytes --- p.55 / Chapter 2.1.5.2 --- Preparation of medium and binding buffer --- p.56 / Chapter 2.1.5.3 --- Preparation of 125I-labelled vasoactive peptides --- p.56 / Chapter 2.1.6 --- MEASUREMENT OF CELLULAR CYCLIC AMP --- p.57 / Chapter 2.1.7 --- DETERMINATION OF PROTEIN CONTENT OF CULTURED ASTROCYTES --- p.60 / Chapter 2.2 --- METHODS --- p.61 / Chapter 2.2.1 --- LIGAND BINDING: MEASUREMENT OF 125I-AM AND 125I-CGRP BINDING / Chapter 2.2.1.1 --- Binding kinetics --- p.61 / Chapter 2.2.1.2 --- Determination of specific binding of 125I-AM and 125I-CGRP --- p.61 / Chapter 2.2.1.3 --- Competition binding studies --- p.62 / Chapter 2.2.2 --- "BIOCHEMICAL INTERACTIONS BETWEEN ET3, AM, CGRP AND PKC-ANALOG" / Chapter 2.2.2.1 --- Determination of the production of cAMP in response to AM and CGRP --- p.62 / Chapter 2.2.2.2 --- Determination of the effect of PMA on AM and CGRP-dependent CAMP production --- p.63 / Chapter 2.2.2.3 --- Determination of the effect of the phorbol esters on AM and CGRP-dependent cAMP production --- p.63 / Chapter 2.2.2.4 --- Elucidation of antagonistic effect of staurosporine and Ro31-8220 --- p.64 / Chapter 2.2.2.5 --- Determination of the effects of ET-3 on AM and CGRP- dependent CAMP accumulation --- p.64 / Chapter 2.2.2.6 --- Determination of the effects of PKC inhIBition on ET-3 suppression of AM- and CGRP-induced CAMP responses --- p.64 / Chapter 2.2.2.7 --- Elucidation of antagonistic effect of cycloheximide --- p.65 / Chapter 2.3 --- STATISTIC ANALYSIS --- p.65 / Chapter CHAPTER 3 --- RESULTS / Chapter 3.1 --- BINDING KINETICS OF 125I-AM AND 125I-CGRP --- p.68 / Chapter 3.2 --- SPECIFIC BINDING OF 125I-AM AND 125I-CGRP --- p.68 / Chapter 3.3 --- COMPETITION BINDING --- p.68 / Chapter 3.4 --- DOSE RESPONSE OF ADRENOMEDULLIN AND CGRP- STIMULATED CAMP PRODUCTION --- p.69 / Chapter 3.5 --- EFFECTS OF PHORBOL ESTERS ON AM AND CGRP DEPENDENT CAMP ACCUMULATION --- p.69 / Chapter 3.6 --- EFFECT OF PMA ON AM AND CGRP-DEPENDENT CAMP ACCUMULATION --- p.70 / Chapter 3.7 --- EFFECT OF ET-3 ON AM AND CGRP-DEPENDENT CAMP ACCUMULATION --- p.70 / Chapter 3.8 --- "THE EFFECTS OF STAUROSPORINE, RO 31-8220" --- p.71 / Chapter 3.9 --- EFFECT OF CYCLOHEXIMIDE ON THE SUPPRESSIVE ACTION OF ET3 --- p.72 / Chapter CHAPTER 4 --- DISCUSSION --- p.73 / Chapter CHAPTER 5 --- GENERAL CONCLUSION --- p.80 / REFERENCES --- p.83 / APPENDIX-PUBLISHED PAPER
46

Impairment of calcitonin gene-related peptide (CGRP)-induced hypotensive responses in vivo and vasorelaxant responses in vitro in rat models of aging, diabetes mellitus and ovariectomy.

January 2001 (has links)
Chan Hoi-Huen. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2001. / Includes bibliographical references (leaves 104-123). / Abstracts in English and Chinese. / Abstract --- p.i / Acknowledgements --- p.v / Publications --- p.vi / Table of contents --- p.viii / List of Figures --- p.xii / List of Tables --- p.xiv / Abbreviations --- p.xv / Chapter Chapter 1 --- Introduction --- p.1 / Chapter 1.1 --- Blood vessels and blood pressure --- p.1 / Chapter 1.2 --- Smooth muscle --- p.2 / Chapter 1.3 --- Endothelium --- p.3 / Chapter 1.4 --- Vasodilation and Vasoconstriction --- p.5 / Chapter 1.5 --- Calcitonin gene-related peptide (CGRP) --- p.6 / Chapter 1.5.1 --- Discovery of CGRP --- p.6 / Chapter 1.5.2 --- Localization and distribution of CGRP --- p.7 / Chapter 1.5.3 --- Structure profile of CGRP --- p.8 / Chapter 1.5.4 --- CGRP and the vascular system --- p.10 / Chapter 1.6 --- Nitric oxide --- p.11 / Chapter 1.6.1 --- Production of NO by nitric oxide synthase (NOS) --- p.12 / Chapter 1.6.2 --- Actions of NO in smooth muscle --- p.14 / Chapter 1.6.3 --- Synergism with CGRP --- p.14 / Chapter 1.7 --- Other research of CGRP in the laboratory of Professor Ronald R. Fiscus --- p.15 / Chapter 1.8 --- "Aging, diabetes mellitus, sex hormones and cardiovascular system" --- p.16 / Chapter 1.9 --- Aim of study --- p.18 / Chapter Chapter 2 --- Methods and materials --- p.19 / Chapter 2.1 --- General experimental methods --- p.19 / Chapter 2.1.1 --- Measurement of blood pressure in anaesthetized rats --- p.19 / Chapter 2.1.2 --- Tissue bath experiments --- p.20 / Chapter 2.1.2.1 --- Preparation of isolated rat aortic rings --- p.20 / Chapter 2.1.2.2 --- Measurement of contractile and relaxant responses in the rat aortic rings --- p.21 / Chapter 2.1.3 --- Culture of aortic rat vascular smooth muscle cells --- p.22 / Chapter 2.1.4 --- Immunostaining for smooth muscle α-actin in cultured smooth muscle cells --- p.23 / Chapter 2.1.5 --- Determination of nitrite levels in smooth muscle cell culture media --- p.24 / Chapter 2.1.6 --- Measurement of protein contents --- p.25 / Chapter 2.1.7 --- Reversed Transcription- Polymerase Chain Reaction (RT-PCR) --- p.26 / Chapter 2.1.7.1 --- mRNA isolation --- p.26 / Chapter 2.1.7.2 --- Reverse transcription (RT) --- p.27 / Chapter 2.1.7.3 --- Polymerase chain reaction (PCR) --- p.27 / Chapter 2.1.7.4 --- Agarose slab gel electrophoresis --- p.29 / Chapter 2.1.7.5 --- Capillary electrophoresis --- p.29 / Chapter 2.2 --- Reagents --- p.30 / Chapter Chapter 3 --- Impairment of hypotension to calcitonin gene-related peptide in female rats with streptozotocin-induced diabetes mellitus or ovariectomy --- p.40 / Chapter 3.1 --- Introduction --- p.40 / Chapter 3.2 --- Methods --- p.45 / Chapter 3.2.1 --- Animal Preparation --- p.45 / Chapter 3.2.2 --- Statistical analysis --- p.46 / Chapter 3.3 --- Results --- p.47 / Chapter 3.3.1 --- "Body weight, blood glucose and initial blood pressure" --- p.47 / Chapter 3.3.2 --- Hypotensive responses to CGRP in ovariectomized rats --- p.48 / Chapter 3.3.3 --- Hypotensive responses to CGRP in diabetic rats --- p.49 / Chapter 3.3.4 --- Hypotensive responses to CGRP in rats with diabetes and ovariectomy --- p.50 / Chapter 3.4 --- Discussion --- p.50 / Chapter 3.5 --- Conclusions --- p.56 / Chapter Chapter 4 --- Severe impairment of CGRP-induced hypotension in vivo and vasorelaxation in vitro in elderly rats --- p.61 / Chapter 4.1 --- Introduction --- p.61 / Chapter 4.2 --- Methods --- p.64 / Chapter 4.2.1 --- Tissue preparation for vascular rings --- p.64 / Chapter 4.2.2 --- Vasorelaxation studies in vitro --- p.65 / Chapter 4.2.3 --- Animal preparation for in vivo studies --- p.65 / Chapter 4.2.4 --- Measurement of hypotensive responses to CGRP --- p.66 / Chapter 4.2.5 --- Statistical analysis --- p.66 / Chapter 4.3 --- Results --- p.67 / Chapter 4.3.1 --- Effect of age on CGRP-induced vasorelaxations in rings of thoracic aorta and caudal arteries --- p.67 / Chapter 4.3.2 --- Effect of age on acetylcholine-induced responses in aortic rings --- p.68 / Chapter 4.3.3 --- CGRP-induced hypotension in young female and male rats --- p.68 / Chapter 4.3.4 --- CGRP-induced hypotension in elderly female and male rats --- p.68 / Chapter 4.3.5 --- CGRP-induced hypotension in elderly female rats with ovariectomy --- p.69 / Chapter 4.4 --- Discussion --- p.69 / Chapter 4.5 --- Conclusions --- p.73 / Chapter Chapter 5 --- "Effects of CGRP on interleukin-Iβ-, lipopolysaccharides- and ginseng extract-induced production of nitrite oxide in vascular smooth muscle cells of elderly rats" --- p.82 / Chapter 5.1 --- Introduction --- p.82 / Chapter 5.2 --- Methods --- p.83 / Chapter 5.2.1. --- Animal model --- p.83 / Chapter 5.2.2. --- Culture of vascular smooth muscle cells --- p.84 / Chapter 5.2.3 --- Extraction of total RNA --- p.84 / Chapter 5.2.4 --- Reverse transcription and polymerase chain reaction (RT-PCR) --- p.35 / Chapter 5.2.5 --- Capillary electrophoresis with laser-induced fluorescence detector (CE-LIF) --- p.85 / Chapter 5.2.6 --- Determination of nitrite levels in smooth muscle cell culture media --- p.85 / Chapter 5.2.7 --- Measurement of protein contents --- p.86 / Chapter 5.3 --- Results --- p.86 / Chapter 5.3.1 --- "Effects of IL-Iβ, alone and in combination with CGRP, on NO production in young and elderly VSMCs" --- p.86 / Chapter 5.3.2 --- "Effects of LPS, alone and in combination with CGRP, on NO production in young and elderly VSMCs" --- p.89 / Chapter 5.3.3 --- "Effects of ginseng extract, alone and in combination with CGRP, on NO production in VSMCs" --- p.89 / Chapter 5.4 --- Discussion --- p.90 / Chapter 5.5 --- Conclusions --- p.93 / Chapter Chapter 6 --- General discussion and Conclusions --- p.100 / References --- p.104
47

Cellular Mechanisms Mediating the Actions of Nerve Growth Factor in Sensory Neurons

Park, Kellie Adrienne 08 August 2007 (has links)
Indiana University-Purdue University Indianapolis (IUPUI) / Nerve growth factor (NGF) is a neurotrophin upregulated with injury and inflammation. Peripheral administration of NGF causes hyperalgesia and allodynia in animals. Blocking NGF signaling reverses these effects. At the cellular level, chronic exposure of sensory neurons to NGF enhances expression the neurotransmitter, calcitonin gene-related peptide (CGRP). Acute exposure to NGF increases capsaicin-evoked CGRP release from sensory neurons in culture. Thus, NGF increases peptide release from neurons by: (1) increasing expression of peptides, and/or (2) altering their sensitivity. The increase in peptide outflow by either mechanism could contribute to development of hyperalgesia and allodynia. The signaling cascades mediating the actions of NGF in sensory neurons are unclear. Therefore, experiments were designed to determine which pathways regulate changes in iCGRP content and evoked release from primary sensory neurons in culture. The Ras/MEK/ERK cascade was identified as a possible regulator of iCGRP expression in response to NGF. To test this pathway, it was manipulated in neurons by (1) expression of dominant negative or constitutively active isoforms of Ras, (2) farnesyltransferase inhibition, (3) manipulation of the RasGAP, synGAP, and (4) blocking MEK activity. When the pathway was blocked, the NGF-induced increase in iCGRP expression was attenuated. When the Ras pathway was activated, iCGRP expression increased. These data indicate that Ras, and downstream signaling kinases, MEK and ERK, regulate the NGF-induced increases in CGRP in sensory neurons. To determine which pathway(s) regulate the increase in capsaicin-evoked iCGRP release upon brief exposure to NGF, the Ras/MEK/ERK pathway was manipulated as described above, and pharmacological inhibitors of the PI3 kinase, PLC, and Src kinase pathways were used. There were no differences observed in NGF-sensitization when the Ras and PI3 kinase pathways were inhibited, suggesting these two pathways were not involved. However, when the Src kinase inhibitor PP2 was used, the NGF-induced increase in release was completely blocked. Furthermore, the PKC inhibitor, BIM, also inhibited the sensitization by NGF. This data indicate Src and PKC regulate of sensitivity of sensory neurons in response to brief exposure to NGF. Thus, there is differential regulation of iCGRP content and evoked release from sensory neurons in response to NGF.
48

Análise das indicações de dosagem de calcitonina sérica realizada no Hospital das Clínicas de Botucatu

Ferreira, Deborah Cristina Goulart January 2019 (has links)
Orientador: Gláucia Maria Ferreira da Silva Mazeto / Resumo: Contexto: O carcinoma medular de tireoide (CMT) é um tumor raro, cujo diagnóstico precoce é extremamente relevante uma vez que sua evolução pode ser bastante agressiva. A dosagem sérica de calcitonina pode indicar o diagnóstico do CMT e é utilizada como marcador da presença de doença durante o seguimento dos pacientes. No Hospital das Clínicas da Faculdade de Medicina de Botucatu (HC-FMB), a dosagem do hormônio passou a ser realizada em 2008, sendo sua solicitação de livre acesso. Objetivos: Avaliar as solicitações de dosagem de calcitonina sérica no HC-FMB, independentemente do diagnóstico ou procedimento terapêutico realizados. Pacientes e Métodos: Foram avaliadas, retrospectivamente, todas as dosagens de calcitonina realizadas no Laboratório de Análises Clínicas do HC-FMB, no período de setembro de 2008 a junho de 2017. Foram então comparados os casos com calcitonina detectável ou não, aqueles com e sem CMT e os casos com solicitação de dosagem considerada adequada ou inadequada/não informada. Foi ainda quantificado o custo com as dosagens adequadas e inadequadas/não informadas. Resultados: Foram realizadas 1453 dosagens de calcitonina, em 915 pacientes, com concentrações detectáveis que variaram de 2,00 pg/mL a 527,00 pg/mL (mediana= 4,1 pg/mL). A mais frequente justificativa da coleta foi nódulo tireoidiano (73,9%). Dezenove pacientes (2,1%) apresentaram diagnóstico final de CMT. A maior parte dos casos apresentou calcitonina indetectável (82,7%). A maioria dos pacientes... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Context: Medullary thyroid cancer (MTC) is a rare tumor, which early diagnosis is extremely relevant since its evolution can be quite aggressive. Serum calcitonin dosage may indicate the diagnosis of MTC and is used as a marker of the disease presence during the patients’ follow-up. At the Clinics Hospital of the School of Medicine of Botucatu (HC-FMB), the dosage of the hormone was first carried out in 2008, being its request of free access. Objectives: To evaluate the serum calcitonin dosage requirements in the HC-FMB, regardless of the diagnostic or therapeutic procedure carried out. Patients and Methods: All calcitonin dosages carried out at the Clinical Analysis Laboratory of HC-FMB from September 2008 to June 2017 were retrospectively evaluated. The cases with or without detectable calcitonin, as well as the cases with or without MTC, and the cases with adequate or inadequate/not informed dosage request were then compared. Costs with appropriate and inadequate/not informed dosages were also quantified. Results: 1453 calcitonin dosages have been carried out in 915 patients with detectable concentrations ranging from 2.00 pg/mL to 527.00 pg/mL (median = 4.1 pg/mL). The most frequent justification for the collection was thyroid nodule (73.9%). Nineteen patients (2.1%) were eventually diagnosed with MTC. The majority of cases had undetectable calcitonin (82.7%). The majority of MTC patients (73.7%) had detectable calcitonin, and 42.1% of those patients had concentrations ab... (Complete abstract click electronic access below) / Mestre
49

"Avaliação da citotoxicidade do alendronato de sódio e da calcitonina em cultura de fibroblastos humanos" / Citotoxicity analyses of sodium alendronate and calcitonin on cultured human fibroblasts

Labate, Julieta Baccetti 15 March 2006 (has links)
As reabsorções radiculares externas são conseqüências decorrentes de lesões traumáticas severas como a avulsão e a intrusão. O estudo de medicamentos que possam auxiliar no controle e prevenção desses processos é de grande interesse. O objetivo desse estudo foi avaliar a citotoxicidade do alendronato de sódio e da calcitonina, aplicados em forma de pasta em cultura de fibroblastos humanos de gengiva. Foi utilizado para o experimento meio condicionado pelas substâncias a serem testadas, divididas em quatro grupos: alendronato de sódio (ALN) a 10-6M; ALN a 10-7M; ALN a 10-8M; e calcitonina (CAL). Como grupos controle usou-se meio de cultura não condicionado e meio de cultura condicionado apenas pelo veículo das pastas (talco farmacêutico e solução salina). A sobrevivência celular foi analisada pelo método de contagem de células viáveis nos tempos experimentais de 1 e 24 horas. Os resultados foram analisados estatisticamente e mostraram que o veículo empregado e as pastas de ALN nas concentrações de 10-7 e 10-8 M não apresentaram diferença significante do grupo controle. Conclui-se que os produtos oriundos das pastas formuladas com ALN a 10-6 M e com CAL a 0,002% apresentaram citotoxicidade para fibroblastos de gengiva humana na forma e período empregados. / External root resorption is a common consequence of dental trauma injuries, mainly in dental avulsion and extrusion. Doubtful prognoses awake the interesting in studying medications, which could help in controlling and preventing these resorption processes. The aim of this study was to evaluate the citotoxicity of sodium alendronate (ALN) and calcitonin, used in a paste formulation in human gingival fibroblasts. Products leached from the pastes were divided into four experimental groups and had conditioned cellular medium: ALN 10-6 M, ALN 10-7 M, ALN 10-8 M and calcitonin 0,002%. Such groups were taking under: fresh media and conditioned media with vehicle (talcum powder and saline). On experimental times, 1 and 24 hours, citotoxicity analyses were performed using the Trypan blue dye exclusion assay. The results were statistically analyzed and showed that the vehicle used and ALN concentrations 10-7 M and 10-8 M did not lead to differences from the control group with fresh media. In contrast, the calcitonin and the ALN pastes in a higher concentration, 10-6 M, demonstrated cell growth reduction. In conclusion, this research showed that products leached from pastes with calcitonin and ALN 10-6 were cytotocic for human gingival fibroblasts in vitro. Meanwhile, substances leached from ALN 10-7 M and 10-8 M were biocompatible.
50

Action and interaction of calcitonin gene-related peptide and nitric oxide on vascular smooth muscle. / CUHK electronic theses & dissertations collection / Digital dissertation consortium

January 1999 (has links)
Lu Lifang. / "November 1999." / Thesis (Ph.D.)--Chinese University of Hong Kong, 1999. / Includes bibliographical references (p. (192-228). / 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 Company, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web. / Mode of access: World Wide Web.

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