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.