Shimokawa H, Vanhoutte P M
Department of Physiology and Biophysics, Mayo Clinic, Rochester, Minnesota 55905.
Am J Physiol. 1989 Apr;256(4 Pt 2):H968-73. doi: 10.1152/ajpheart.1989.256.4.H968.
Dietary supplementation with cod-liver oil significantly augments endothelium-dependent relaxations in porcine coronary arteries. The present study was designed to examine the effect of dietary administration of omega 3 polyunsaturated fatty acids (mainly eicosapentaenoic acid, the major component of fish oil) on endothelium-dependent relaxations in porcine coronary arteries. Male Yorkshire pigs were maintained 4 wk on a regular diet with or without supplementation with purified eicosapentaenoic acid (3.5 g/day) and docosahexaenoic acid (1.5 g/day). Endothelium-dependent relaxations were examined in vitro. In rings from the treated group, endothelium-dependent relaxations were augmented in response to bradykinin, serotonin, and ADP, but not to the calcium ionophore A23187. These augmentations were not altered by indomethacin but were significantly inhibited by methylene blue, an inhibitor of guanylate cyclase. In the treated group, endothelium-dependent relaxations to aggregating platelets also were significantly augmented; platelet-induced contractions of quiescent rings were inhibited more by the presence of the endothelium than in arteries from the control group. Bioassay experiments demonstrated that the release of endothelium-derived relaxing factor(s) by bradykinin and relaxations of the vascular smooth muscle to the factor(s) were greater in arteries from the treated group. These observations indicate that dietary omega 3 polyunsaturated fatty acids augment receptor-operated endothelium-dependent relaxations, partly due to the augmented release of endothelium-derived relaxing factor(s) and partly due to the augmented relaxation of the vascular smooth muscle to the factor(s).
用鱼肝油进行膳食补充可显著增强猪冠状动脉的内皮依赖性舒张。本研究旨在探讨膳食给予ω-3多不饱和脂肪酸（主要是二十碳五烯酸，鱼油的主要成分）对猪冠状动脉内皮依赖性舒张的影响。雄性约克夏猪在常规饮食条件下饲养4周，饮食中添加或不添加纯化的二十碳五烯酸（3.5克/天）和二十二碳六烯酸（1.5克/天）。体外检测内皮依赖性舒张。在处理组的血管环中，对缓激肽、5-羟色胺和ADP的内皮依赖性舒张增强，但对钙离子载体A23187的反应未增强。这些增强作用不受吲哚美辛影响，但被鸟苷酸环化酶抑制剂亚甲蓝显著抑制。在处理组中，对聚集血小板的内皮依赖性舒张也显著增强；与对照组动脉相比，内皮的存在对血小板诱导的静息血管环收缩的抑制作用更强。生物测定实验表明，缓激肽释放的内皮源性舒张因子以及血管平滑肌对该因子的舒张反应在处理组动脉中更强。这些观察结果表明，膳食ω-3多不饱和脂肪酸增强受体介导的内皮依赖性舒张，部分原因是内皮源性舒张因子释放增加，部分原因是血管平滑肌对该因子的舒张反应增强。
