Abstract:Aim To observe the role of Ghrelin on myocardial metabolism key enzyme AMP-activated protein kinase (AMPK) signaling pathway. Methods Goto-Kakizaki (GK) rats (8-week-old males) were randomly divided into three groups with 8 rats in each group: GK group,metformin group(received metformin 350 mg/kg),and Ghrelin group (received Ghrelin 200 μg/kg in twice daily). Normal male Wistar kyoto rats (n8) served as normal controls. Four weeks later,the effects of Ghrelin on cardiac remodeling were evaluated by echocardiographic,hemody- namicand gene expression analysis (AMPK,Glut4 mRNA expression). Results After 4 weeks,compared with Wistar rats and GK group,heart rate reduced,diastolic,systolic function improved in Ghrelin group (P<0.05) HOMA-IR index was lower than the GK rats in Ghrelin group (P<0.05) Myocardial mitochondria and myocardial microvascular of Ghrelin group rats were close to Wistar group. Myocardial AMPKα2,Glut4 mRNA expression levels were significantly increased in Ghrelin group compared with GK group (P<0.05). Conclusions Intraperitoneal injection of Ghrelin can reduce the spontaneous GK rats insulin resistance,and improve left ventricular diastolic and systolic function. Its mechanism may be associated with longer-term increase of AMPK expression of myocardial cell and the promotion of the glucose transporter.