缬沙坦和苯那普利对自发性高血压大鼠心肌钠泵和钙泵的影响

目的 比较缬沙坦和苯那普利对自发性高血压大鼠(SHR) 心肌Na⁺-K⁺-ATP 酶和Ca²⁺-ATP 酶活性的影响。方法 将24 只雄性14 周龄SHR 分为生理盐水组、苯那普利1 mg·kg^-1 组、缬沙坦8 mg·kg^-1组和缬沙坦24 mg·kg^-1 组, 每组6 只,并另设6 只同龄雄性Wistar Kyoto 大鼠作为对照。分析Na⁺-K⁺-ATP 酶和Ca²⁺-ATP 酶活性变化。结果 (1) SHR 的心肌Na⁺-K⁺-ATP 酶1.99±0.57和Ca²⁺-ATP 酶活性2.25±0.46均低于WKY大鼠3.43±0.62、4.35±0.60;(2) 缬沙坦和苯那普利对心肌Na⁺-K⁺-ATP 酶活性起增加作用;(3)Ca²⁺-ATP 酶活性的提高仅见于24 mg·kg^-1 缬沙坦组。结论 SHR 心肌Na⁺-K⁺-ATP 酶和Ca²⁺-ATP 酶均呈受抑状态, 缬沙坦和苯那普利均能改善心肌Na⁺-K⁺-ATP 酶活性, 但对Ca²⁺-ATP 酶改善仅见于较大剂量的缬沙坦。

Effect of valsartan and benazepril on the activities of Na+-K+pump and Ca2+ pump in the myocardium of SHR

Aim To observe the effect of valsartan and benazepril on the activities of Na⁺-K⁺-ATPase and Ca²⁺-ATPase in myocardium of spontaneously hypertensive rats (SHR).Methods Twenty-four SHR were divided into the NS, benazepril, valsartan 8 mg·kg^-1 and valsartan 24 mg·kg^-1 groups, with 6 Wistar Kyoto rats(WKY) serving as control.after 4 experimental weeks, the activi ties of Na⁺-K⁺-ATPase, and Ca²⁺-ATPase as well as associated indexes were measured.Results (1) The activities of Na⁺-K⁺-ATPase and Ca²⁺-ATPase in myocardium of SHR were no tably lower than those of WKY rats; (2) Both valsartan and benazepril increased activity of Na⁺-K⁺-ATPase in myocardium of SHR;(3) The increase of activity of Ca²⁺-ATPase was observed only in 24 mg·kg^-1 valsartan group.Conclusion Valsartan and benazepril elevate the activity of Na⁺-K⁺-ATPase in myocardium of SHR.But the elevation of Ca²⁺-ATPase activity is observed only in large dose of valsartan.