肉桂对糖尿病性心肌病大鼠的心脏保护作用

目的探讨肉桂对糖尿病性心肌病大鼠的心脏保护作用。方法 SD大鼠一次性腹腔注射85 mg/kg链脲佐菌素建立糖尿病模型,进而诱发心肌损伤,同时设立正常对照组。模型动物随机分为模型组、卡托普利组(50 mg/kg)和肉桂组(0.75 g/kg)。灌胃给药26天后,将动物麻醉,采用多道生理信号采集处理系统测量心电图;分离左心室并称重,计算左心质量指数(LVWI);全自动生化分析仪检测血清葡萄糖(GLU)、总胆固醇(TC)、三酰甘油(TG)、高密度脂蛋白(HDL)和低密度脂蛋白(LDL)水平;ELISA法检测血清脑钠尿肽(BNP)水平;定磷法检测心肌组织Na~+K~+-ATP酶和Ca~(2+)Mg~(2+)-ATP酶的活性;HPLC检测心肌能量产物磷酸肌酸(PCr)、三磷酸腺苷(ATP)、二磷酸腺苷(ADP)和单磷酸腺苷(AMP)含量。结果与正常组相比,模型组大鼠的左心质量指数和血清GLU、TC、TG、LDL和BNP水平显著升高,心电图QRS波群、P-R、S-T和Q-T间期延长,心率减慢,心肌组织Na~+K~+-ATP酶、Ca~(2+)Mg~(2+)-ATP酶活性和PCr、ATP、ADP、AMP含量显著降低。与模型组相比,肉桂组大鼠血清TC、TG、LDL和BNP水平显著降低,心电图QRS波群、P-R间期明显缩短,心肌组织Ca~(2+)Mg~(2+)-ATP酶活性和PCr、ATP和ADP含量显著升高。结论肉桂可能通过影响心肌能量代谢改善糖尿病大鼠的心肌损伤。

Cardioprotective effects of Rougui(Cinnamomi Cortex) on diabetic cardiomyopathy in rats

  Objective:To investigate the cardioprotective effects of Rougui(Cinnamomi Cortex) on diabetic cardiomyopathy in rats. MethodsThe diabetes model in SD rats was established by single intraperitoneal injection of streptozotocin(STZ) at a dose of 85 mg/kg,which then induced myocardial injury. The normal rats were taken as the normal group. The model animals were randomly divided into the model group,captopril group(50 mg/kg) and Rougui group(0.75 g/kg),and were treated with corresponding drugs by intragastric administration. After treatment for 26 days,the animals were anesthetized and the electrocardiogram(ECG) of rats was measured by multichannel physiological signal acquisition and processing system. The left ventricle was separated and weighed,and the left ventricular weight index(LVWI) was calculated. The serum levels of blood glucose(GLU),total cholesterol(TC),triglyceride(TG),high density lipoprotein(HDL) and low density lipoprotein(LDL) were detected by automatic biochemical analyzer. The serum level of brain natriuretic peptide(BNP) was detected by ELISA. The activities of Na⁺K⁺-ATP and Ca²⁺Mg²⁺-ATP enzymes in myocardial tissue were detected by phosphorus quantitation. The contents of phosphocreatin(PCr),adenosine triphosphate(ATP),adenosine monophosphate(ADP) and adenosine monophosphate(AMP) in myocardium were tested by high performance liquid chromatography(HPLC).  Results:Compared with the normal group,the LVWI and the serum levels of GLU,TC,TG,LDL and BNP were significantly increased,and the intervals of QRS,P-R,S-T and Q-T were prolonged in the model group. In addition,the heart rate was slowed down,and the activities of Na⁺K⁺-ATP and Ca²⁺Mg²⁺-ATP enzymes in myocardial tissue and the contents of PCr,ATP,ADP and AMP were significantly decreased. Compared with the model group,the serum levels of TG,TC,LDL and BNP were significantly decreased,the intervals of QRS and P-R were significantly shortened,the Ca²⁺Mg²⁺-ATP enzyme activity and the contents of PCr,ATP and ADP in myocardial tissue were increased significantly in the Rougui group.  Conclusion:Rougui(Cinnamomi Cortex) may improve the myocardial injury in diabetic rats through the effects on energy metabolism of myocardium.