红杉醇对2型糖尿病大鼠心肌损伤的保护作用

目的：探讨红杉醇（sequoyitol，Seq）对2型糖尿病大鼠心肌损伤的保护作用。方法：采用高脂高糖饮食加小剂量链脲佐菌素（ STZ，30 mg/kg）腹腔注射诱导2型糖尿病大鼠模型，灌服Seq[12．5、25、50 mg/（kg· d）]。治疗6周后，于末次给药后测定血糖及左心室质量指数、血清乳酸脱氢酶（LDH）、磷酸肌酸激酶（CPK）活性、C-反应蛋白（CRP）水平及心肌一氧化氮（ NO）、丙二醛（ MDA）含量；Masson染色观察大鼠心肌胶原纤维变化；免疫组化检测心肌诱导型一氧化氮合酶（ iNOS）蛋白表达。结果：Seq各剂量组能降低模型大鼠血糖及左心室质量指数，改善心肌纤维化，降低CK、LDH、CRP水平，下调心肌iNOS蛋白表达，降低心肌NO及MDA含量（ P＜0．05或P＜0．01）。结论：Seq可能通过抗氧化机制，下调心肌iNOS表达，进而对糖尿病大鼠心肌损伤产生保护作用。

Protective effect of sequoyitol on myocardial injury in type 2 diabetic rats

Objective：To investigate the protective effects of sequoyitol on myocardial injury in type 2 diabetic rats.Methods：The animal models of type 2 diabetes were developed by feeding with high fat and high sugar diet as well as intraperitoneal injection of small dose of streptozotocin （STZ,30 mg/kg）.After administration of sequoyitol [12.5,25,50 mg/（kg· d）] for 6 weeks,the contents of blood glucose（BG）and left ventricular mass index, serum lactate dehydrogenase （ LDH ） , creatine phosphocreatine kinase（CRK）,C-reactive protein（CRP）,myocardial ni-tric oxide（ NO） and malondialdehyde（ MDA） were determined by the final treatment.Masson staining was used to detect the changes of myocardial collagen fibers,and immunohistochemistry to determine the expression of inducible nitric oxide synthase （ iNOS ） protein in the myocardium . Results：Different dosage of sequoyitol was capable of bringing down the BG levels and left ventricular mass index,improving the myocardial fibro-sis,reducing levels of CK,LDH and CRP,down-regulating the content of myocardial iNOS,NO and MDA in model rats（P〈0.05 or P〈0.01）. Conclusion：Sequoyitol appears to be protective effects on the myocardium in type 2 diabetic rats through down-regulating the expression of myocar-dial iNOS protein and potentially lessening the myocardial damage in-duced by oxidative stress.