Lippton H L, Chapnick B M, Hyman A L, Glass F L, Kadowitz P J
Peptides. 1981 Summer;2(2):165-9. doi: 10.1016/s0196-9781(81)80030-7.
The effects of indomethacin, a cyclooxygenase inhibitor, on vasodilator responses to bradykinin and nitroglycerin were investigated in the peripheral vascular bed of the anesthetized cat. Intra-arterial injections of bradykinin and nitroglycerin elicited dose-related decreases in mesenteric and hindquarters vascular resistance. Mesenteric vasodilator responses to nitroglycerin in absolute units were unchanged 30 min after administration of indomethacin whereas responses to bradykinin expressed as an absolute mm Hg decrease in perfusion pressure were increased. Indomethacin was also without effect on vasodilator responses to lower doses of nitroglycerin whereas responses to higher doses of nitroglycerin and bradykinin in absolute units were enhanced in the hindquarters vascular bed. Indomethacin increased vascular resistance in the mesenteric and hindquarters vascular beds and decreased systemic vasodepressor responses to the prostaglandin precursor, arachidonic acid. When the increase in (initial value) vascular resistance was taken into account by expressing vasodilator responses on a percent decrease basis, indomethacin only enhanced the vasodilator response to the highest does of bradykinin studies. Result of the present study suggest that products in the cyclooxygenase pathway may serve to maintain the peripheral vascular bed of the cat in a dilated state but that these metabolites do not mediate vasodilator responses to bradykinin. The present data further suggest that products in the cyclooxygenase pathway may play a minor role in modulating the dilator effects of bradykinin in the mesenteric and hindquarters vascular beds of the cat.
在麻醉猫的外周血管床中，研究了环氧化酶抑制剂吲哚美辛对缓激肽和硝酸甘油血管舒张反应的影响。动脉内注射缓激肽和硝酸甘油可引起肠系膜和后肢血管阻力呈剂量相关的降低。吲哚美辛给药30分钟后，肠系膜对硝酸甘油的血管舒张反应以绝对单位计无变化，而以灌注压绝对毫米汞柱降低表示的对缓激肽的反应增强。吲哚美辛对较低剂量硝酸甘油的血管舒张反应也无影响，而在后肢血管床中，对较高剂量硝酸甘油和缓激肽的反应以绝对单位计增强。吲哚美辛增加了肠系膜和后肢血管床的血管阻力，并降低了对前列腺素前体花生四烯酸的全身血管减压反应。当通过以百分比降低为基础表示血管舒张反应来考虑（初始值）血管阻力的增加时，吲哚美辛仅增强了对所研究的最高剂量缓激肽的血管舒张反应。本研究结果表明，环氧化酶途径中的产物可能有助于维持猫的外周血管床处于扩张状态，但这些代谢产物并不介导对缓激肽的血管舒张反应。目前的数据进一步表明，环氧化酶途径中的产物在调节猫肠系膜和后肢血管床中缓激肽的舒张作用方面可能起次要作用。
