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Anatomia estrutural e ultraestrutural dos gânglios celíaco e mesentérico superior em humanos / Structural and ultrastructural anatomy of the superior celiac and mesenteric ganglions in humansLima, Regiane Freire Nogueira de 23 November 2018 (has links)
Os gânglios pertencentes ao Sistema Nervoso Autônomo (SNA) estão divididos em grupos de acordo com sua localização. Os gânglios celíaco e mesentérico superior são gânglios simpáticos pré-vertebrais. Estes se localizam anteriormente à coluna vertebral e à aorta abdominal ao nível das vértebras T12 a L1. Conectando o Sistema Nervoso Central (SNC), por meio dos nervos esplênico maior e menor, ao Sistema Nervoso Periférico (SNP), formando um emaranhado de nervos denominado plexo nervoso. Ambos participam do controle da motilidade gastrointestinal, sendo assim, estão envolvidos na fisiopatologia dos distúrbios inerentes ao seu território de inervação. Foram dissecados e fixados a solução de formol a 4%, 33 blocos anatômicos de seres humanos contendo a parte abdominal da aorta e o pâncreas, obtidos de 15 indivíduos do gênero masculino e 18 do feminino com idades variando de 20 a 90 anos, divididos em três grupos: Grupo I (jovens - 20 a 40: 3 homens e 4 mulheres); Grupo II (adulto - 45 a 60: 8 homens e 6 mulheres) e Grupo III (idosos - 70 a 90: 4 homens e 8 mulheres), onde avaliou-se aspectos estruturais e ultraestruturais dos gânglios celíacos e mesentérico superior, quanto à sua topografia e componentes microscópicos por meio das colorações de Hematoxilina e Eosina, Tricromo de Masson, Violeta Cresil, Verhoff e Picro-Sirius, observou-se respectivamente, a identificação geral dos componentes ganglionares, fibra elástica e o componente colágeno ganglionar, assim como análises por método de Microscopia Eletrônica de Varredura (MET). Quanto ao aspecto macroscópico os gânglios celíacos foram contados em número de 58, sendo 25 espécimes (86% dos casos) apresentaram-se bilateralmente de formato retangular, 7 (12%) estavam fusionados na linha mediana, e 1 (1,7%) no antímero esquerdo, ambos de aspecto irregular. Relativamente todos pertencentes a este antímero estavam em situação inferior aos do antímero direito. Já o gânglio mesentérico superior, de formato preferencialmente estrelado, ocorreu em 10 espécimes (30%) ele estava situado anteriormente à artéria mesentérica superior, e em 17 (51%), posteriormente a ela, em 3 casos foi encontrado um entrecruzamento de fibras nervosas espessas com presença de corpos celulares espaçados, e em 3 casos (9%), o gânglio não foi encontrado, apenas um emaranhado de feixes com fibras nervosas. Referente a parte qualitativa, notou-se que à medida que o ser humano envelhece há uma diminuição das fibras colágenas do tipo III, passando a predominar fibras do tipo I nos grupos: GII e GIII e quantitativamente, foram analisados 9 gânglios sendo 3 de cada grupo: GI (20-40: 2 homens e 1 mulher); GII (45-60: 3 homens) e GIII (70-90: 3 mulheres), embora não se tenha realizado uma análise estatística a média das áreas dos nervos do GIII foi maior em relação ao GI, por outro lado as áreas dos fascículos nervosos não exibiram diferenças aparentes. A área do corpo neuronal de GI, GII e GIII houve uma progressiva diminuição desse parâmetro nos grupos GII e GIII. O material foi fornecido pelo Sistema de Verificação de Óbito da Capital SP (SVOC-SP/USP) e após a sua coleta as peças foram processadas no Laboratório de Anatomia Funcional Aplicada a Clínica e à Cirurgia (LAFACC) do Departamento de Anatomia do Instituto de Ciências Biomédicas III da Universidade de São Paulo (ICB III USP). O estudo estrutural e ultraestrutural de gânglios simpáticos em humanos abre perspectivas futuras para pesquisas correlacionadas a morfologia e sua função. Os resultados podem ter importância para a neurociência humana, dando embasamento para tratamentos de doenças relacionadas ao trato gastrointestinal (TGI), o que pressupõe grande relevância deste estudo. / The ganglia belonging to the Autonomic Nervous System (ANS) are divided into groups according to their location. The superior celiac and mesenteric ganglia are pre-vertebral sympathetic ganglia. These are located anterior to the vertebral column and to the abdominal aorta at the level of the vertebrae T12 to L1. Connecting the Central Nervous System (CNS), via the major and minor splenic nerves, to the Peripheral Nervous System (SNP), forming a tangle of nerves called the nervous plexus. Both are involved in the control of gastrointestinal motility and are therefore involved in the pathophysiology of the disorders inherent to their territory of innervation. A total of 33 human anatomical blocks containing the abdominal part of the aorta and the pancreas, obtained from 15 male and 18 female subjects with ages varying from 20 to 90 years, divided into three groups: Group I (young - 20 to 40: 3 men and 4 women); Group II (adult - 45 to 60: 8 men and 6 women) and Group III (elderly - 70 to 90: 4 men and 8 women), where structural and ultrastructural aspects of the celiac and mesenteric superior ganglia were evaluated for their topography and microscopic components through the staining of Hematoxylin and Eosin , Masson\'s trichrome, Violet Cresil, Verhoff and Picro-Sirius, the general identification of the ganglionic components, elastic fiber and the ganglionic collagen component, as well as the Scanning Electron Microscopy (MET) method were observed. As to the macroscopic aspect, the celiac ganglia were counted in 58, 25 specimens (86% of the cases) were bilaterally rectangular, 7 (12%) were fused at the median line, and 1 (1,7%) in the antimer left, both of irregular appearance. Relatively all belonging to this antimer were inferior to those of the right antimer. The superior mesenteric ganglion, with a predominantly star-shaped shape, occurred in 10 specimens (30%), located anterior to the superior mesenteric artery, and in 17 (51%), posterior to it, in 3 cases a \"cross-linking\" of and in 3 cases (9%), the ganglion was not found, only a tangle of bundles with nerve fibers. Regarding the qualitative part, it was noticed that as the human being grows older there is a decrease of type III collagen fibers, and type I fibers predominate in the groups: GII and GIII and quantitatively, 9 glands were analyzed, 3 in each group: GI (20-40: 2 men and 1 woman); GII (45-60: 3 men) and GIII (70-90: 3 women), although no statistical analysis was performed the mean of the GIII nerve areas was higher in relation to the GI; on the other hand, the areas of the nerve fascicles showed no apparent differences. The area of the neuronal body of GI, GII and GIII showed a progressive decrease of this parameter in the GII and GIII groups. The material was supplied by the São Paulo State Capital Surveillance System (SVOC-SP / USP) and after its collection the pieces were processed in the Laboratory of Functional Anatomy Applied to Clinic and Surgery (LAFACC) of the Department of Anatomy of the Institute of Biomedical Sciences III of the University of São Paulo (ICB III - USP). The structural and ultrastructural study of sympathetic ganglia in humans opens future perspectives for research correlated with morphology and its function. The results may be important for human neuroscience, giving support to treatments of diseases related to the gastrointestinal tract (GIT), which presupposes great relevance of this study.
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Minimally Invasive Approach to Vascular Compression of The DuodenumAhmed, Aws E., Strand, Matthew S., Iannitti, David A. 25 April 2023 (has links)
Complete or partial obstruction of the duodenum by the superior mesenteric artery (SMA) is a rare cause of bowel obstruction. SMA syndrome results from the compression of the 3rd part of the duodenum between the superior mesenteric artery and the abdominal aorta. Causes include anatomical variation in the superior mesenteric artery, trauma, burns, surgeries, malignancy, and rapid weight loss. Diagnosis of SMA syndrome in patients may be difficult, as the clinical findings often resemble other forms of small bowel obstructions. This syndrome was first described in the literature by Carl Freiherr von Rokitansky in 1861. Subsequently, David Wilke provided a comprehensive description of the disease in a series of 75 patients. There has been skepticism about the existence of SMA syndrome due to scant literature reports and non-specific symptomatology. However, modern cross-sectional imaging has confirmed the existence of this rare syndrome. Here we present the case of a 50-year-old female with longstanding symptoms of gastrointestinal discomfort, weight loss, nausea, and vomiting. She underwent an exhaustive gastrointestinal workup until a diagnosis of SMA syndrome was made. We elected to proceed with a minimally invasive three-port laparoscopic, trans-mesenteric side-to-side duodenojejunostomy. The patient was discharged on postoperative day one after tolerating a regular diet. On one month follow-up, our patient reported improvement in symptoms with no postprandial pain or nausea and normal bowel movements. In conclusion, we report a case of superior mesenteric artery syndrome in a patient with recurrent abdominal pain and nausea. CT scan has the highest sensitivity for the diagnosis of SMA syndrome, findings suggestive of the diagnosis include an abnormal aortomesenteric angle and distance. While supplemental tube feeds and gastric drainage may resolve the condition without the need for surgery, this often takes many weeks to months to be effective. Minimally invasive surgical bypass is an attractive option because of the rapidity of symptom resolution, lack of need for long-term invasive tubes, short inpatient length of stay, and high success rate.
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Localization of α7 Nicotinic Acetylcholine Receptor mRNA and Protein Within the Cholinergic Anti-Inflammatory PathwayDowns, A. M., Bond, C. E., Hoover, D. B. 25 April 2014 (has links)
Electrical stimulation of the vagus nerve attenuates tumor necrosis factor (TNF) synthesis by macrophages and reduces the systemic inflammatory response. Current evidence suggests that the α7 nicotinic acetylcholine receptor present in the celiac/superior mesenteric ganglia is a key component in vagus nerve signaling to the spleen; however, there is currently no direct anatomical evidence that the α7 receptor is present in the murine celiac/superior mesenteric ganglia. Our study addresses this deficiency by providing anatomical evidence that the α7 receptor is expressed within the celiac/superior mesenteric ganglia and splenic nerve fibers using immunohistochemistry and quantitative polymerase chain reaction (qPCR). α7 receptor mRNA is highly expressed in the celiac/superior mesenteric ganglia and at low levels in the spleen compared to the brain. Double-labeling for α7 and tyrosine hydroxylase shows that α7 receptor protein is present on noradrenergic neurons within the ganglia and prejunctionally on noradrenergic nerve fibers within the spleen. The α7 receptor in the ganglia provides a possible location for the action of α7-selective agonists, while prejunctional α7 receptor expressed on splenic nerves may induce an increase in norepinephrine release in a positive feedback system enhanced by lymphocyte-derived acetylcholine.
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Kepenų arterijų anatominiai variantai ir jų įtaka viršutinės pasaito arterijos hemodinamikai / Anatomical variants of the hepatic arteries and their influence on superior mesenteric artery hemodynamicsSamuilis, Artūras 02 May 2011 (has links)
Kepenų arterijų anatominiai variantai yra dažni. Viena dažniausių aberantinių (netipiškai atsišakojančių) kepenų arterijų atsišakojimo vietų yra viršutinė pasaito arterija. Pastarosios arterijos kraujotaka yra įtakojama daugybės fiziologinių ir patologinių veiksnių. Literatūroje taip pat aprašyti pavieniai atvejai apie iš viršutinės pasaito arterijos atsišakojančios aberantinės kepenų arterijos įtaką viršutinės pasaito arterijos hemodinamikai, tačiau didesnės apimties įrodymais pagrįstų tyrimų šioje srityje iki šiol nebuvo atlikta. Todėl šio tyrimo tikslas buvo įvertinti, ar aberantinė kepenų arterija, atsišakojanti iš viršutinės pasaito arterijos, reikšmingai įtakoja pastarosios kraujagyslės hemodinamiką.
Šiame tyrime kompiuterinės tomografijos angiografijos pagalba įvertinti kepenų arterijų anatominiai variantai, atrinkti pacientai doplerio ultragarso tyrimams. Pastaruoju metodu tirta viršutinės pasaito arterijos kraujotaka pacientams, kurių vieni turėjo aberantinę kepenų arteriją, atsišakojančią iš viršutinės pasaito arterijos, o kiti turėjo įprastą kepenų arterijų anatomiją. Vertinta aberantinės kepenų arterijos, atsišakojančios iš viršutinės pasaito arterijos, įtaka pastarosios arterijos hemodinamikai (rezistentiškumui).
Remiantis tyrimo duomenimis nustatyta, kad kepenų arterijų anatominiai variantai yra dažni. Aberantinė kepenų arterija, atsišakojanti iš viršutinės pasaito arterijos, reikšmingai mažina pastarosios arterijos rezistentiškumą. Pateiktos praktinės... [toliau žr. visą tekstą] / Anatomical variants of hepatic arteries are frequent. One of the most common origins of aberrant (atypically branching) hepatic arteries is superior mesenteric artery. Many physiologic and pathologic features influence hemodynamics of the latter artery. There were some sporadic cases in literature about the influence of aberrant hepatic artery arising from superior mesenteric artery to the hemodynamics of the latter artery, but no evidence based large extent studies were performed. Therefore the aim of this study was to evaluate how significant the aberrant hepatic artery branching from the superior mesenteric artery influences the hemodynamics of superior mesenteric artery.
Anatomical variants of the hepatic arteries were evaluated by computed tomography angiography also the candidates for Doppler ultrasound were selected. Doppler ultrasound was used to evaluate the hemodynamics of the superior mesenteric artery in patients with aberrant hepatic artery arising from the superior mesenteric artery and in those with typical hepatic artery anatomy. The influence of the aberrant hepatic artery arising from superior mesenteric artery to the hemodynamics (resistance) of the superior mesenteric artery was assessed.
The results of the investigation show that anatomical variants of the hepatic arteries are frequent. The aberrant hepatic artery arising from superior mesenteric artery significantly lowers resistance of the superior mesenteric artery. Practical recommendations were set... [to full text]
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On Acute Thrombo-Embolic Occlusion of the Superior Mesenteric ArteryAcosta, Stefan January 2004 (has links)
<p>Acute thrombo-embolic occlusion of the superior mesenteric artery (SMA) with intestinal infarction is a lethal disease, difficult to diagnose in time, with unknown incidence and cause-specific mortality. The aim of this thesis was to characterize the disease and to develop diagnostic methods. </p><p>Two laboratory studies were conducted on patients with suspected acute SMA occlusion. A pilot-study showed that the fibrinolytic marker D-dimer was elevated in six patients with the disease. In the subsequent study including 101 patients, D-dimer was the only elevated coagulation marker in nine patients with the disease. In a prospective study 24 patients (median age 84 years) were identified, of whom four were diagnosed at autopsy, despite an autopsy-rate of 10%. One-fourth were initially nursed in non-surgical wards. Length of the intestinal infarction was a predictor for death. An analysis of patients from the three studies showed that D-Dimer was elevated in all 16 tested patients with the disease.</p><p>Sixty patients with acute SMA occlusion underwent intestinal revascularisation and were registered in the Swedish Vascular Registry (SWEDVASC). One-year survival-rate was 40%. Previous vascular surgery was a negative risk-factor.</p><p>A population-based study was conducted in Malmö, based on an autopsy-rate of 87%. Among 270 patients with the disease, 2/3 were diagnosed only at autopsy and 1/2 were managed in non-surgical wards. The incidence was 8.6 per 100000 person years. The age-standardized incidence increased exponentially without gender differences. The diagnosis was the cause of death in 1.2% among octogenarians and beyond. Thrombotic occlusions were located proximally within the SMA and associated with extensive intestinal infarctions. Synchronous embolism, often multiple, occurred in 2/3 of the patients with embolic occlusions.</p><p>Conclusions: A normal D-dimer at presentation most likely excludes the diagnosis. Acute SMA occlusion was more frequent than previously estimated from clinical series. The patients were often nursed in non-surgical wards.</p>
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On Acute Thrombo-Embolic Occlusion of the Superior Mesenteric ArteryAcosta, Stefan January 2004 (has links)
Acute thrombo-embolic occlusion of the superior mesenteric artery (SMA) with intestinal infarction is a lethal disease, difficult to diagnose in time, with unknown incidence and cause-specific mortality. The aim of this thesis was to characterize the disease and to develop diagnostic methods. Two laboratory studies were conducted on patients with suspected acute SMA occlusion. A pilot-study showed that the fibrinolytic marker D-dimer was elevated in six patients with the disease. In the subsequent study including 101 patients, D-dimer was the only elevated coagulation marker in nine patients with the disease. In a prospective study 24 patients (median age 84 years) were identified, of whom four were diagnosed at autopsy, despite an autopsy-rate of 10%. One-fourth were initially nursed in non-surgical wards. Length of the intestinal infarction was a predictor for death. An analysis of patients from the three studies showed that D-Dimer was elevated in all 16 tested patients with the disease. Sixty patients with acute SMA occlusion underwent intestinal revascularisation and were registered in the Swedish Vascular Registry (SWEDVASC). One-year survival-rate was 40%. Previous vascular surgery was a negative risk-factor. A population-based study was conducted in Malmö, based on an autopsy-rate of 87%. Among 270 patients with the disease, 2/3 were diagnosed only at autopsy and 1/2 were managed in non-surgical wards. The incidence was 8.6 per 100000 person years. The age-standardized incidence increased exponentially without gender differences. The diagnosis was the cause of death in 1.2% among octogenarians and beyond. Thrombotic occlusions were located proximally within the SMA and associated with extensive intestinal infarctions. Synchronous embolism, often multiple, occurred in 2/3 of the patients with embolic occlusions. Conclusions: A normal D-dimer at presentation most likely excludes the diagnosis. Acute SMA occlusion was more frequent than previously estimated from clinical series. The patients were often nursed in non-surgical wards.
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Acute Occlusion of the Superior Mesenteric Artery : Diagnosis and treatmentBlock, Tomas January 2010 (has links)
Acute occlusion of the superior mesenteric artery (SMA) is a condition associated with high mortality and morbidity. The aim of this thesis is to evaluate diagnostic and therapeutic approaches for acute SMA occlusion. In a prospective study of patients with suspected intestinal ischemia, no biomarker was sufficiently accurate to detect this condition. In a second retrospective study, pancreatic amylase and troponin-I were elevated in a substantial proportion of patients with verified SMA occlusion. In an experimental animal model of acute SMA occlusion, microarray studies of ischemic small bowel wall were used to characterize the mRNA response to ischemia. Thrombospondin, Monocyte Chemoattractant Protein 1 and Gap Junction Alpha 1 were consistently up-regulated in all pigs with intestinal ischemia. Genes encoding previously proposed biomarkers for intestinal ischemia were either up-regulated, such as lactate dehydrogenase and creatine kinase, or down-regulated, such as intestinal fatty acid binding protein and glutathione S-transferase. In a study of the role of computed tomography in the diagnosis of SMA occlusion, it was shown that computed tomography with intravenous contrast was associated with improved survival. A retrospective analysis of all acute SMA revascularizations in Sweden 1999-2006 revealed that D-dimer was elevated in all 35 measured cases. Endovascular surgery was associated with better outcome than open surgery, both in short and in long term. The presence of postoperative short bowel syndrome was a strong independent risk-factor for decreased long-term survival. Conclusions: Data affirm that D-dimer may serve as an exclusion test for acute SMA occlusion, whereas elevated troponin-I and pancreatic amylase are potential diagnostic pitfalls. Contrast-enhanced computed tomography of the visceral arteries seems to be the best diagnostic method. Endovascular surgery is an option to open surgery in selected cases, and was associated with favourable outcome.
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Anatomical variants of the hepatic arteries and their influence on superior mesenteric artery hemodynamics / Kepenų arterijų anatominiai variantai ir jų įtaka viršutinės pasaito arterijos hemodinamikaiSamuilis, Artūras 02 May 2011 (has links)
Anatomical variants of hepatic arteries are frequent. One of the most common origins of aberrant (atypically branching) hepatic arteries is superior mesenteric artery. Many physiologic and pathologic features influence hemodynamics of the latter artery. There were some sporadic cases in literature about the influence of aberrant hepatic artery arising from superior mesenteric artery to the hemodynamics of the latter artery, but no evidence based large extent studies were performed. Therefore the aim of this study was to evaluate how significant the aberrant hepatic artery branching from the superior mesenteric artery influences the hemodynamics of superior mesenteric artery.
Anatomical variants of the hepatic arteries were evaluated by computed tomography angiography also the candidates for Doppler ultrasound were selected. Doppler ultrasound was used to evaluate the hemodynamics of the superior mesenteric artery in patients with aberrant hepatic artery arising from the superior mesenteric artery and in those with typical hepatic artery anatomy. The influence of the aberrant hepatic artery arising from superior mesenteric artery to the hemodynamics (resistance) of the superior mesenteric artery was assessed.
The results of the investigation show that anatomical variants of the hepatic arteries are frequent. The aberrant hepatic artery arising from superior mesenteric artery significantly lowers resistance of the superior mesenteric artery. Practical recommendations were set... [to full text] / Kepenų arterijų anatominiai variantai yra dažni. Viena dažniausių aberantinių (netipiškai atsišakojančių) kepenų arterijų atsišakojimo vietų yra viršutinė pasaito arterija. Pastarosios arterijos kraujotaka yra įtakojama daugybės fiziologinių ir patologinių veiksnių. Literatūroje taip pat aprašyti pavieniai atvejai apie iš viršutinės pasaito arterijos atsišakojančios aberantinės kepenų arterijos įtaką viršutinės pasaito arterijos hemodinamikai, tačiau didesnės apimties įrodymais pagrįstų tyrimų šioje srityje iki šiol nebuvo atlikta. Todėl šio tyrimo tikslas buvo įvertinti, ar aberantinė kepenų arterija, atsišakojanti iš viršutinės pasaito arterijos, reikšmingai įtakoja pastarosios kraujagyslės hemodinamiką.
Šiame tyrime kompiuterinės tomografijos angiografijos pagalba įvertinti kepenų arterijų anatominiai variantai, atrinkti pacientai doplerio ultragarso tyrimams. Pastaruoju metodu tirta viršutinės pasaito arterijos kraujotaka pacientams, kurių vieni turėjo aberantinę kepenų arteriją, atsišakojančią iš viršutinės pasaito arterijos, o kiti turėjo įprastą kepenų arterijų anatomiją. Vertinta aberantinės kepenų arterijos, atsišakojančios iš viršutinės pasaito arterijos, įtaka pastarosios arterijos hemodinamikai (rezistentiškumui).
Remiantis tyrimo duomenimis nustatyta, kad kepenų arterijų anatominiai variantai yra dažni. Aberantinė kepenų arterija, atsišakojanti iš viršutinės pasaito arterijos, reikšmingai mažina pastarosios arterijos rezistentiškumą. Pateiktos praktinės... [toliau žr. visą tekstą]
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Mecanismos de sinalização endotelial envolvidos na atividade cardiovascular do α-terpineol / Endothelial signaling mechanisms involved in cardiovascular effect to α-terpineol in hypertensive rats.Ribeiro, Thaís Pôrto 27 February 2012 (has links)
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Previous issue date: 2012-02-27 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / The essential oils are volatile organic constituents found in aromatic plants, which present several monoterpenes, such a-terpineol. Studies have demonstrated some biologic activities such as hypotensive and vasorelaxant (Guedes et al., 2004). In the present work the cardiovascular effects of a-terpineol was investigated and the pharmacodynamics of this effect was characterized. Wistar Kyoto and spontaneously hypertensive rats (SHR) were anaesthetized and polyethylene catheters were inserted into the low abdominal aorta and inferior vena cava for blood pressure measurements and administration of drugs. Isolated superior mesenteric rings (1-2 mm) were suspended by cotton threads for isometric tension recordings in Tyrode s solution (37°C, gassed with 95% O2 and 5% CO2), under 0.75g resting tension were measured by using pressure transducers, coupled to a computer set and CVMS software Miobath-4, WPI, Sarasota, EUA. In addition, the bioavailability of NO and eNOS, AKT and AMPK activity were quantified when exposing cells to α-terpineol in the cultured endothelial cells. In both SHR and normotensive rats, i.v. bolus injections of α-terpineol (1 20 mg/kg) decreased mean arterial pressure (MAP) in a dose-related manner, WKY (-103, -399, -5211, -6212 mmHg, n=10) and SHR (-375, -577, -715, -844 mmHg, n=9) associated with tachycardia. However, hypotensive and tachycardic responses were significantly attenuated after L-NAME (20 mg/kg, i.v.). The -terpineol demonstrated improves the baroreflex sensitivity. In intact isolated rat mesenteric rings -terpineol (10-12 10-5M) induced concentration-dependent relaxation of the contractions induced by phylephrine (10M) WKY Emax= 60 4 or SHR Emax= 53.7 ± 3, p<0.05, n=9). After endothelium removal the vasorelaxant elicited by -terpineol was significantly attenuated WKY [Emax= 20.5 1*] and SHR [Emax= 16.1 ± 3*, p<0.05, n=8]. Similar results were obtained in the presence of L-NAME 100M, a competitive antagonist of NOS, hydroxocobalamin 30 μM, a NO scavenger or ODQ 10μM, a selective inhibitor of soluble guanylyl cyclase. In addition, in endothelial cells, a-terpineol increased eNOS activation and NO levels by phosphorylation of PI3K/ AKT and AMPK pathway. However, atropine (1ηM) or indometacin (10 μM) had no effect on the a-terpineol -induced vasorelaxation. Furthermore, vasorelaxation was significantly attenuated in the presence of 20 mM KCl a modulator K+ efflux or several blocking of potassium channels: 1mM 4-aminopirimidine, 10 M glibenclamide, 1 mM tetraethylammonium and carybdotoxin plus apamin (0.2uM). In conclusion, the present study demonstrated that a-terpineol induced hypotensive effect, probably due to a decrease of peripheral vascular resistances, which seems to be mediated by endothelium derived relaxant factors, at least NO induced. These results suggest that vasorelaxant response, almost completely mediated by the endothelium, likely via NO release and activation eNOS by PI3K and AMPK with consequently activation of NO-cGMP pathway and potassium channels activation at least, KCa, KV, and KATP are involved in the vasorelaxant effect induced by a-terpineol. / Os óleos essenciais são componentes voláteis orgânicos encontrados em plantas aromáticas, que apresentam vários monoterpenos, como o α-terpineol. Estudos têm demonstrado algumas atividades biológicas, tais como hipotensivas e vasorelaxantes (Guedes et al., 2004). No presente trabalho, estudaram-se os efeitos cardiovasculares do α-terpineol e caracterizou-se a farmacodinâmica destes efeitos. Para isso foram utilizados ratos normotensos Wistar (WKY) e espontaneamente hipertensos (SHR), empregando técnicas combinadas in vivo, in vitro, e cultivo de células endoteliais. Para determinar a medida direta da pressão arterial, foram implantados cateteres na artéria aorta e veia cava inferior para administração de drogas em ratos WKY e SHR. Adicionalmente, foram realizados estudos para avaliar a reatividade vascular, assim, animais foram sacrificados e a artéria mesentérica superior foi isolada. Os anéis foram mantidos em cubas com solução de Tyrode, e gaseificada com carbogênio. Os anéis foram fixados a um transdutor de força, o qual estava acoplado a um sistema de aquisição de dados (Miobath-4, WPI, Sarasota, EUA) a uma tensão de 0,75 g por 1h. Após este período as preparações, foram pré-contraídas com 10 μM de fenilefrina (FEN) e, em seguida, concentrações crescentes de a-terpineol (10-12-10-5 M) foram adicionadas cumulativamente. Adicionalmente, realizamos experimentos para quantificação da produção de NO e determinação da atividade da eNOS, AKT e AMPK em cultivo de células endoteliais, utilizando as técnicas de citometria de fluxo e western blotting. Assim, observamos que a-terpineol (1, 5, 10 e 20 mg/kg i.v., randomicamente) produziu uma hipotensão dose-dependente em ratos WKY (-103, -399, -5211, -6212 mmHg, n=10) e SHR (-375, -577, -715, -844 mmHg, n=9, respectivamente), associada a taquicardia. A resposta hipotensora foi atenuada significantemente, após o tratamento com L-NAME (20 mg/kg, i.v), sugerindo que esse efeito pode ser decorrente de uma diminuição da resistência periférica., α-terpineol demonstrou melhorar a sensibilidade do barorreflexo. A resposta vasorelaxante foi significativamente atenuada quando comparada aos anéis na presença (WKY Emax= 60 4 e SHR Emax= 53,7 ± 3, p<0,05, n=9) e na ausência do endotélio funcional [WKY Emáx= 20,5 1 e SHR Emáx=16,1 ± 3, p<0,05, n=8]. Em anéis pré-contraídos com FEN na presença de L-NAME (100 μM), Hidroxicobalamina (30 μM) e ODQ (10 μM), a resposta relaxante foi atenuada significantemente, sugerindo uma participação da via NO-GMPc. Adicionalmente, a-terpineol aumentou os níveis de produção de NO e a atividade da eNOS por fosforilar vias como a PI3K e AMPK. No entanto, na presença de atropina (1 mM) ou indometacina (10 uM), a resposta vasorelaxante de a-terpineol não foi alterada indicando que os receptores muscarínicos e metabólitos da enzima Ciclooxigenase parecem não estar envolvidos. KCl (20mM) foi capaz de atenuar o efeito de a-terpineol, e preparações com endotélio vascular incubados com glibenclamida (10 uM) e 4-aminopiridina (1 mM), tetraetilamônio (1 mM) e caribdotoxina + apamina (0,2 μM). Deste modo, concluímos que resposta vasorelaxante promovida pelo a-terpineol é dependente de endotélio e envolve a via L-Arginina-NO-GMPc por aumentar a fosforilação da eNOS por vias PI3K e AMPK, produção de NO e EDHF com participaçãode canais para potássio do tipo KCa, KV e KATP em SHR e WKY e estes efeitos são responsáveis por eventos in vivo.
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Participação da via do óxido nítrico na resposta relaxante induzida por E- cinamaldeído-oxima em artéria mesentérica superior isolada de rato. / Participation of nitric oxide pathway in relaxation response induced by E- cynnamaldheyde-oxime in superior mesenteric artery isolated from rats.Veras, Robson Cavalcante 30 August 2009 (has links)
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Previous issue date: 2009-08-30 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior - CAPES / Decreased availability of NO in the vasculature promotes the progression of cardiovascular diseases and oximes represents a NO-donor group capable of to restore this defictIn rat superior mesenteric arterial rings, as non-aromatic oximes: diacetylmonoxime and dimetylglycone-oxime, as aromatic oximes: benzofenone-oxime, 4-Cl-benzofenone and cinnamaldheyde-oxime isomeric mixture were markedly less potent than tans-E-cinnamaldheyde-oxime (E CAOx) whose relaxation was concentration-dependent in denuded-endothelum pre-contracted rings with PHE (pD2 = 5,11 ± 0,05), or U46619 (pD2 = 5,03 ± 0,06), an tromboxanic agonist TP, or with A23187 (pD2 = 4,70 ± 0,06), an Ca2+ ionophore, beyond KCl 60mM (pD2 = 4,50 ± 0,06). The relaxation was not modified by endothelium or L-NAME (100 μM, NOS inhibitor), proadifen (30 M; inibidor do citocromos P450), ou de N-acetyl-L-Cysteyn (1 mM e 3 mM; an NO- scavenger). However, was affected by cytochromos P4501A1 and NADPH-dependent reductases inhibitor, 7ethoxyresorufin (7 ER, 10 μM; pD2 = 4,82 ± 0,07), and NO scavenger, PTIO (300 M; pD2 = 4,68 ± 0,11). Demonstrating that E-CAOx induces independent-endothelium relaxation with a possible NO production, mediated by NADPH-dependent reductases. These results corroborate with E-CAOx action of to increase DAF-T fluorescence, in rat aorta smooth miocytes, abolished by 7-ER pre-incubation. Futhermore, the Emax decrease caused by (Rp)-8pCPT-cGMPS (10 M; PKG inhibitor), plus potency reduction by ODQ presence (0,1 M; pD2 = 4,65 ± 0,07 e 10 M; pD2 = 4,41 ± 0,04), a soluble guanylyl-cyclase inhibitor, reforce the pathway NO/cGC/cGMP/PKG participation. On the other hand, the presences of KCl 20mM and TEA (1 mM; pD2 = 4,62 ± 0,04), a BKCa blocker, were capable of the interfering in response, but not 4-AP (1 mM; Kv blocker) and Glibenclamide (10 M; a KATP blocker). In ODQ (10 M) combinations, only KCl 20mM, interpose on Emax, suggesting that K+ channels contribution, majorly BKCa, is sGC-activation dependent. Due relaxing pre-contracted rings: with S(-)BayK 8644 (pD2 = 4,95 ± 0,05), a direct activator of dihydropiridine-sensitive Cav, and rings pre-contracted with PHE in the presence of Niphedipine (1 M), E-CAOx can also to be acting by inhibits Ca2+ influx through dihydropiridine-sensitive Cav or to interfere in contract mechanisms ulterior to Ca2+ entry, as is the case of Na+/Ca2+ exchanger. This hypothesis is justified by reduction in response due the Ni+2 presence (Na+/Ca2+ inhibitor). In conclusion, the data shown that E-CAOx was the more potent oxime investigated with NO production thougth NADPH-dependent reductases action and subsequentely pathway CGs/GMPc/PKG activation associated to BKCa activation, Cav inhibition and exchalenger Na+/Ca2+activation. / Uma diminuição da disponibilidade do NO na vasculatura promove a progressão de doenças vasculares e as oximas representam um grupo de doadores de NO capaz de reestabelecer tal deficiência. Em anéis de artéria mesentérica superior isolada de rato, tanto as oximas não aromáticas: diacetilmonoxima e dimetilglioxima, quanto as oximas aromáticas: benzofenona-oxima, 4 Cl benzofenona-oxima e a mistura isômera de cinamaldeído-oximas foram menos potentes que trans-cinamaldeído-oxima (E-CAOx) cujo relaxamento foi dependente de concentração em anéis pré-contraídos com: FEN (pD2 = 5,11 ± 0,05), um agonista adrenérgico, ou com U46619 (pD2 = 5,03 ± 0,06), um agonista tromboxânico TP, ou com A23187 (pD2 = 4,70 ± 0,06), um ionóforo de íons Ca2+, além de KCl 60mM (pD2 = 4,50 ± 0,06). O relaxamento não foi modificado pela presença do endotélio ou de L-NAME (100 M; inibidor das sintases de NO), proadifeno (30 M; inibidor do citocromos P450), ou de N-acetil-L-cisteína (1 mM e 3 mM; seqüestrador de NO-). Entretanto, foi afetado pela presença do inibidor de citocromos P4501A1 e de redutases dependentes de NADPH, 7-Etoxi-resurofino (7-ER, 10 M; pD2 = 4,82 ± 0,07), e do sequestrador de NO, PTIO (300 M; pD2 = 4,68 ± 0,11). Demonstrando que E-CAOx causa um relaxamento independente de endotélio com possível produção de NO , mediado por redutases dependentes de NADPH. Tais resultados corroboram com a ação de E-CAOx em aumentar a fluorescência emitida por DAF-T, em mióciotos de aorta de rato, abolida pela presença de 7-ER (10 M). Além disso, a diminuição do efeito máximo de E-CAOx causada pela presença de (Rp)-8pCPT-cGMPS (10 M; inibidor da PKG), somada à diminuição da potência causada pelo ODQ (0,1M; pD2 = 4,65 ± 0,07 e 10M; pD2 = 4,41 ± 0,04), um inibidor da ciclase de guanilil solúvel (CGs), reforçam a participação da via NO/CGs/GMPc/PKG. Por outro lado, as presenças de KCl 20mM (pD2 = 4,78 ± 0,04) e de TEA (1 mM; pD2 = 4,62 ± 0,04), um bloqueador de BKCa, foram capazes de interferir na resposta, mas 4-aminopiridina (1 mM; bloqueador de Kv) e Glibenclamida (10 M; bloqueador de KATP) não. Em combinações com ODQ (10M), apenas KCl 20 mM, interferiu no Emax, sugerindo que a contribuição dos canais para K+, principalmente dos BKCa, é dependente da ativação da CGs. Por relaxar anéis pré-contraídos com S(-)BayK 8644 (pD2 = 4,95 ± 0,05), um ativador direto dos Cav sensíveis à diidropiridinas, e anéis pré-contraídos com FEN na presença de nifedipino (1 M; inibidor dos Cav), E-CAOx pode também estar atuando por inibir o influxo de íons Ca2+ ou interferir em mecanismos contráteis posteriores à entrada de Ca2+, como é o caso do trocador Na+/Ca2+. Tal hipótese é justificada pela redução da resposta provocada pela presença do Ni+2 (inibidor do trocador Na+/Ca2+). Em conclusão, os dados demonstram que E-CAOx foi a oxima investigada mais potente e que produz NO via ação das redutases dependentes de NADPH com subseqüente ativação da via CGs/GMPc/PKG associada à ativação dos BKCa, inibição dos Cav e ativação do trocador Na+/Ca2+.
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