依那普利和厄贝沙坦对去势后大鼠心肌肥厚一氧化氮和一氧化氮合酶的影响

Effects of enalapril and irbesartan on NO and NOS in ovariectomized rats with myocardial hypertrophy

目的探讨依那普利(Enalapril)和厄贝沙坦(Irbesartan)对去势后大鼠心肌肥厚一氧化氮(NO)和一氧化氮合酶(nitric oxide synthase,NOS)的影响。方法雌性SD大鼠卵巢切除术(ovariectomy,OVX)1周行腹主动脉缩窄术(abdominal aortic constriction,AAC)后3d,随机分成6组:假手术组、假OVX+AAC组、OVX+AAC+NS组、OVX+AAC+雌二醇组、OVX+AAC+依那普利组、OVX+AAC+厄贝沙坦组。连续给药25d,检测大鼠心脏质量指数(heartmass index,HMI)、左心室质量指数(LVMI)、心肌匀浆NO、总NOS、诱导型一氧化氮合酶(iNOS)及结构型一氧化氮合酶(cNOS)水平。结果①与假手术组比较,OVX+AAC+NS组和OVX+AAC+雌二醇组的LVMI和HMI增大(P<0.05);与OVX+AAC+NS组比较,OVX+AAC+依那普利组和OVX+AAC+厄贝沙坦组的LVMI和HMI显著降低(P<0.05)。②与假手术组比较,OVX+AAC+NS组的心肌总NOS、cNOS水平降低,而心肌iNOS水平升高(P<0.05);与OVX+AAC+NS组比较,OVX+AAC+依那普利组和OVX+AAC+厄贝沙坦组可提高心肌组织NO含量,升高总NOS、cNOS水平,降低iNOS水平(P<0.05)。③心肌组织NO和NOS水平呈显著正相关(r=0.854,P<0.01)。结论依那普利和厄贝沙坦可通过调节心肌NOS水平和NO含量,对去势大鼠产生心肌保护作用。

Objective To study the effects of enalapril and irbesartan on the level of nitric oxide （NO） and the activity of nitric oxide synthase （NOS） in ovariectomized rats with myocardial hypertrophy.Methods Three days after ovariectomy（OVX） and abdominal aortic constriction（AAC）,female SD rats were randomly divided into six groups：sham-operation,sham OVX＋AAC,OVX＋AAC＋NS,OVX ＋ AAC ＋ estradiol,OVX＋AAC＋ enalapril and OVX＋AAC＋ irbesartan groups.With drugs intervented for 25 consecutive days,cardial index （LVMI and HMI）,the level of nitric oxide （NO） and the activity of total nitric oxide synthase （NOS）,inducible nitric oxide synthase （iNOS） and construction of nitric oxide synthase （cNOS） of the myocardium were detected.Results ①As compared with sham-operation group,cardial LVMI and HMI were increased in OVX＋AAC＋NS and OVX＋AAC＋estradiol groups（P〈0.05）;however,they were significantly decreased in OVX＋AAC＋ enalapril and OVX＋AAC＋ irbesartan groups as compared to those in OVX＋AAC＋NS group（P〈0.05）.②As compared with sham-operation group,the level of cardial NOS and cNOS were decreased but the level of cardial iNOS increased in OVX＋AAC＋NS group （P〈0.05）.The level of cardial NO,NOS and cNOS were increased but iNOS decreased in OVX＋AAC＋ Enalapril and OVX＋AAC＋ Irbesartan groups as compard to those in OVX＋AAC＋NS group（P〈0.05）.③The level of cardial NO had significant positive correlation to the activity of NOS（r=0.854,P〈0.01）.Conclusion Enalapril and irbesartan have the protecting effect on myocardium of the ovariectomized rats.