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Medical AI Inquiry: You was designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.  Labels: OBJECTIVE, METHODS, RESULTS. Meshes: Animals, Calcium Channels, Endothelin-1, Heparin, Hepatorenal Syndrome, In Vitro Techniques, Inositol 1,4,5-Trisphosphate Receptors, Kidney, Male, Rats, Rats, Wistar, Receptors, Cytoplasmic and Nuclear, Renal Artery, Tumor Necrosis Factor-alpha, Vasoconstriction.
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Does [ Tumor necrosis factor-alpha enhance the effect of endothelin on renal vasoconstriction in isolated perfused rat kidney ]? Context: To explore the role of tumor necrosis factor-alpha (TNF-alpha) in the pathogenesis of hepatorenal syndrome. By isolated perfused kidney technique, rat kidneys were perfused at a constant flow. Changes in perfusion pressure (mmHg) were consecutively measured with multi-functional physiology recorder. After TNF-alpha or heparin treated 90 minutes, the perfusion pressure stimulated by endothelin-1 (ET-1) was detected. TNF-alpha and heparin didn't modify the baseline perfusion pressure. When ET-1 was added at 2 nmol/L, the perfusion pressures increased to (47+/-9) mmHg, (97+/-36) mm Hg and (11+/-6) mm Hg in control, TNF-alpha and heparin (10mg/L) treated group, respectively, which were different among the three groups (t>or=3.811, P<0.01). No pathological damages were found in kidney tissues from all the groups after being stained with hematoxylin/eosin.
assistant
TNF-alpha plays an important role in the pathogenesis of hepatorenal syndrome by promoting renal vasoconstriction. Final Decision: yes