K_(ATP)通道介导异氟醚所致的冠状动脉细小分支的舒张

ROLE OF ATP-SENSITIVE POTASSIUM CHANNELS IN ISOLATED PORCINE CORONARY ARTERIOLES

目的和方法 :用微血管口径直接测量技术 ,评介挥发性麻醉气体Isoflurane,KATP通道开放剂cromakalim和非特异性血管扩张剂sodiumnitroprusside对猪冠状动脉细小分支直径的作用 ,并研究了KATP通道阻断剂 glibenclamide对血管口径的影响。结果 :Glibenclamide显著阻断Isonurane和cromakalim的血管扩张作用 ,而sodiumnitroprusside则不受影响。结论 :Isoflurane扩张冠状动脉细小分支的作用是由KATP通道所中介的。

Aim: This study is to evaluate the mechanism of isoflurane (Iso) increasing coronary flow. Methods:Thirteen porcine microvessels from the left anterior descending coronary artery were dissected, and placed in an organ chamber, vascular diameter was measured using an optical density,video detection system. Changes in vascular diameter by buffer equilibrated with 1.4% Iso were assessed before, during, and after glibenclamide (Glib). Results: Iso caused pronounced dilation of coronary arterioles, Glib attenuated the effects. Glib blunted the coronary dilating responses during cromakalim (a K ATP channel opener), without effect on those during sodium nitroprusside (a K ATP channel independent vasodilator). Conclusion: Isoflurane causes pronounced coronary dilation and the effect is mediated by the K ATP channels.