ATP-MgCl_2和维拉帕米(Ver)抑制去甲肾上腺素(NE)和KCl所致兔主动脉条收缩反应,使量-效曲线非平行右移,压低最大收缩反应,说明是非竞争性拮抗,而单纯ATP和单纯MgCl_2的拮抗作用不明显。ATP-MgCl_2和Ver选择性抑制电压依赖性钙通道(PDC),抑制细胞内Ca~(++)的释放,但对受体启动性钙通道(ROC)的抑制作用不明显。单纯ATP和单纯MgCl_2的作用均不如ATP-MgCl_2和Ver。 ATP-MgCl 2 and verapamil (Ver) inhibited the contractile response of norepinephrine (NE) and KCl in rabbit aortic strips, resulting in a non-parallel, right-shifting of the volume-effect curve and a decrease in the maximal contraction response, suggesting that it is a non-competitive antagonistic response. However, the antagonistic effect of ATP alone and MgCl 2 alone was not obvious. ATP-MgCl 2 and Ver selectively inhibited voltage-dependent calcium channels (PDC) and inhibited the release of intracellular Ca ++ , but the inhibitory effect on receptor-initiated calcium channels (ROC) was not obvious. Both ATP and MgCl 2 alone are not as effective as ATP-MgCl 2 and Ver.