吉非罗齐拮抗Bay K 8644增加大鼠主动脉平滑肌细胞L-型电压依赖性钙电流

Gemfibrozil Antagonize of Bay K 8644 Increasing Rat Aorta L-Type Voltage-dependent Calcium Currents

关键词:  吉非罗齐  主动脉  L-型电压依赖性钙通道  L-NAME  内皮

Key words:  gemfibrozil  aorta  L-type voltage-dependent calcium channels  L-NAME  endothelium

摘要:

目的 观察吉非罗齐拮抗Bay K 8644对离体大鼠主动脉的收缩效果，并进一步研究其机制。方法 采用离体血管张力记录法记录大鼠主动脉血管环的张力变化，膜片钳电生理学记录大鼠主动脉平滑肌细胞L-型电压依赖性钙电流。结果 Bay K 8644可以引起大鼠主动脉血管环收缩，最大收缩幅度为(2.13±0.42)g，提前孵育吉非罗齐可以对Bay K 8644的收缩幅度起到一定程度的抑制作用，使其收缩幅度降至(1.02±0.36)g。提前孵育L-NAME和去内皮均没有对吉非罗齐的抑制效果产生明显影响。Bay K 8644可以使得大鼠主动脉平滑肌细胞L-型钙电流增大127.62%，而吉非罗齐的干预，可以使其增幅降低到79.48%。结论 吉非罗齐可以一定程度上抑制Bay K 8644引起的大鼠主动脉收缩，其效果不受一氧化氮合酶抑制剂L-NAME及去内皮的影响。吉非罗齐可以部分拮抗Bay K 8644引起的大鼠离体主动脉平滑肌细胞L-型电压依赖性钙电流的增大。

Abstract:

OBJECTIVE To invstigate the myogenic effect of gemfibrozil on rat aorta contraction-induced by Bay K 8644 and to explore the underlying mechanism. METHODS The tension of rat aorta was recorded by PowerLab, and the L-type voltage-gated Ca²⁺ current was recorded by whole-cell patch clamp technique. RESULS Bay K 8644 induced rat aorta contract, the maximal contraction was (2.13±0.42)g, pretreatment gemfibrozil could depress the contraction to (1.02±0.36)g. Pretreatment L-NAME and endothelium-denuded could not affect the contraction induced by Bay K 8644 on rat aorta. Bay K 8644 could increase the L-type voltage-gated Ca²⁺ currents of rat aorta smooth cells by 127.62%, and gemfibrozil depressed the increment to 79.48%. CONCLUSION Gemfibrozil can inhibit the contraction of rat aorta induced by Bay K 8644 in a certain degree, and the effect is not affected by L-NAME nor by endothelium denudation. Gemfibrozil antagonism of Bay K 8644 effects on rat aorta L-type Ca2+channels currents partly.