糖尿病心肌组织中NOS的改变与糖尿病心肌病关系探讨

目的探讨实验性糖尿病(DM)大鼠模型心肌组织中一氧化氮(NO)浓度和一氧化氮合酶(NOS)活性改变在DM心肌病发生和发展中的作用.方法SD大鼠一次注射链脲佐菌素(STZ)建立DM模型,成模后36只DM大鼠分批每两周检测空腹血糖和NO浓度,2、6、10周时进行心肌组织NOS活性检测.结果(1)DM大鼠血清中NO的浓度与对照组相比显著升高(P＜0.01),并随着血糖浓度的升高及时间的延长而升高.(2)DM组大鼠心肌组织NO浓度和NOS的活性均较对照组明显升高(P＜0.05).结论高血糖状态激活了心肌组织中的NOS,使心肌组织中NO过度增加,加上血液中过度升高的NO,损伤了心肌细胞的结构及其功能,可能是DM心肌病产生的重要机制之一.

Relationship between the changes of nitric oxide synthase of the heart tissu e and diabetic cardiomyopathy

Objective To investigate the effects of the changes of nitric oxide(NO)and nitric oxide synthase(NOS) in heart tissue on diabetic cardiomyopathy in the STZ-induced diabetic rats.Methods After established diabetic rats model using STZ,we investigated the serum level of NO every two weeks and NO level and NOS activities in the heart tissue in 2th,6th and 10th week.Results (1)Serum level of NO in diabetic rats showed a significant increase in contrast to normal group ( P <0 01).(2)NO level and NOS activities in myocytes of diabetic rats were increased compared with normal group ( P <0 05).Conclusion Because of hyperglucose state,the increase of NOS activities and NO level in heart tissue,with the higher serum level of NO,impared the cardiac cells' structure and function.This may be an important mechanism in induced diabetic cardiomyopathy.