绞股蓝总苷对糖尿病心肌病大鼠心脏功能的影响

Effects of gypenosides on cardiac function in diabetic cardiomyopathy rats

目的探讨绞股蓝总苷(gypenosides,GP)对糖尿病心肌病大鼠心脏功能的影响。方法SD大鼠50只,随机分为对照组,糖尿病心肌病组,绞股蓝总苷低、中、高剂量治疗组。后4组腹腔注射链脲佐菌素55 mg.kg-1制备糖尿病模型。造型后第7周起,对照组和糖尿病心肌病组给予纯净水,绞股蓝总苷低、中、高剂量治疗组分别给予绞股蓝总苷501、002、00 mg.kg-1.d-1,连续给药6周。第12周末测定大鼠心室内压,分析心功能,电镜观察心肌细胞超微结构改变情况,同时测定心肌一氧化氮含量及一氧化氮合酶、Ca2-+ATP酶和Na+-K-+ATP酶活性。结果糖尿病心肌病组大鼠的左室收缩压、左心室舒张末期压、左室内压最大上升和下降速率、左室内压上升达最大速率所需时间等心功能指标和一氧化氮合酶、Ca2-+ATP酶及Na+-K-+ATP酶活性均明显低于对照组(P<0.01),而绞股蓝总苷中、高剂量治疗组上述指标显著高于糖尿病心肌病组(P<0.05);糖尿病心肌病组心肌细胞肌小节失去正常结构,肌原纤维坏死、溶解,线粒体水肿,嵴消失,绞股蓝总苷中、高剂量可明显减轻上述病变。结论绞股蓝总苷可减轻心肌超微结构损伤,改善糖尿病心肌病大鼠左心室功能。

Objective To investigate the therapeutic effects cle in diabetes. Methods Fifty Sprague-Dawley rats were of gypenosides on the dysfunction of cardiac musrandomly divided into the following groups：Control, diabetic cardiomyopathy and diabetic cardiomyopathy treated with gypenosides. The diabetic cardiomyopathy in rats was induced by injecting streptozotocin （STZ, 55 mg·kg^-1, ip）. Seven weeks after rats suffered from diabetes, they received gypenosides with different dosages （50,100,200 mg·kg^-1·d^-1） orally for six weeks. In the meanwhile, the pure water was given to one group of diabetic and normal rats as controis. Subsequently, the functions of cardiac muscle, such as left ventricular systolic pressure（PLVS）, left ventricular end diastolic pressure （PLVED）, maximal rate of increase and decrease of left ventricular pressure（ ±dp/dtmax）and the time reaching the maximal rate of increase of left ventricular pressure（ t ）, as well as the activities of nitric oxide synthase （NOS）, cardiac Ca^2＋-ATPase and Na^＋-K^＋-ATPase were measured. The ultrastructure of cardiac muscle was examined by using electron microscopy. Results The images of cardiac muscles under electron microscopy in diabetic rats showed the degeneration of myofibrillae and the edema of mitochondria. PLVS, PLVED, ± dp/dtmax and t, as well as the activities of NOS, cardiac Ca^2＋ -ATPase and Na^＋-K^＋-ATPase in rats with diabetic cardiomyopathy were significantly lower than those in controls. The activities of NOS, cardiac ATPases and the function of cardiac muscles in diabetic rats with gypenosides treatment were higher than those without giving gypenosides. The degeneration of myofibrillae was not observed in diabetic rats with gypenosides treatment. Conclusions Gypenosides secure cardiac muscles and their function from diabetic impairment.