Objective:To study the effect of levocarnitine(L-CN) on tissue inhibitor of metalloproteinase-1(TIMP-1) and intercellular adhesion molecule-1(ICAM-1) expression of rats with coronary heart disease and evaluate the protective effect of L-CN on myocardial cells.Methods:Highfat diet feeding and intraperitoneal injection of pituitrin was performed on rats in model group and CHD Model of rats was built.Rats with successful model-building were selected and divided into L-CN group and Ctrl group randomly.Rats in L-CN group were given L-CN treatment,with intraperitoneal injection of 200 mg·kg~(-1)?d~(-1) and successive administration for 3 d.Rats in Ctrl group were given equal volumes of normal saline.Blood was collected from carotid artery at different time and expression quantity of creatine kinase-MB(CK-MB) and Troponin Ⅰ(Tn Ⅰ)in serum was detected.Rats in each group were put to death and were separated to obtain the myocardial tissue.Real-time PCR and Western Blotting hybridization were performed to detect the TIMP-1.ICAM-1 expression in myocardial tissue in each group.Statistical analysis was employed to explore the expression changes of TIMP-1 and ICAM-1.and ELISA test was used lo analyse the expression changes of myocardial necrosis marker- CK-MB and Tn I to learn the effect of L-CN and its myocardial protective effect.Results:The total cholesterol,triglyceride and blood glucose levels of rats in model group were significantly higher than that in control group,which indicated that due to high-fat diet feeding,blood lipid of rats in model group was obviously higher than that in control group.In myocardial tissue of rats in model group,TIMP-I level significantly reduced and ICAM-1 level significantly increased(P<0.0l).In model group,after L-CN treatment.TTMP-I level had double increase,while ICAM-1 level had 43%of decrease in L-CN group compared with Ctrl group.After L-CN intervention treatment.CK-MB and Tn Ⅰ content in L-CN group relatively reduced compared with Ctrl group.The difference among groups was obvious(P<0.01).Condusions:L-CN could increase the TTMP-I expression level and inhibit the ICAM-1 expression level.L-CN has a certain myocardial protective effect Objective: To study the effect of levocarnitine (L-CN) on tissue inhibitor of metalloproteinase-1 (TIMP-1) and intercellular adhesion molecule-1 (ICAM-1) expression of rats with coronary heart disease and evaluate the protective effect of L -CN on myocardial cells. Methods: Highfat diet feeding and intraperitoneal injection of pituitrin was performed on rats in model group and CHD Model of rats was built. Rats with successful model-building were selected and divided into L-CN group and Ctrl group randomly . Rats in L-CN group were given L-CN treatment with intraperitoneal injection of 200 mg · kg -1 d -1 and successive administration for 3 d. Rats in Ctrl group were given equal volumes of normal saline. blood was collected from carotid artery at different time and expression quantity of creatine kinase-MB (CK-MB) and Troponin I (Tn I) in serum was detected. Rats in each group were put to death and were separated to obtain the myocardial tissue. Real-time PCR and Western Blotting hybridization we The performed analysis of TIMP-1 and ICAM-1 and ELISA test was used to analyze the expression changes of myocardial cells necrosis marker-CK-MB and Tn I to learn the effect of L-CN and its myocardial protective effect. Results: The total cholesterol, triglyceride and blood glucose levels of rats in model group were significantly higher than that in control group, which that due to high-fat diet feeding, blood lipid of rats in model group was obviously higher than that in control group. myocardial tissue of rats in model group, TIMP-I level significantly reduced and ICAM-1 level significantly increased (P < 0.0l) .In model group, after L-CN treatment.TTMP-I level had double increase, while ICAM-1 level had 43% of decrease in L-CN group compared with Ctrl group. After L-CN intervention treatment. CK -MB and Tn Ⅰ content in L-CN group relatively reduced compared wit h Ctrlgroup. the difference among groups was obvious (P <0.01) .Condusions: L-CN could increase the TTMP-I expression level and inhibit the ICAM-1 expression level. L-CN has a certain myocardial protective effect