| Objective: To observe the disturbance of glucose metabolism capability, and insulin sensibility and insulin release in chronic congestive heart failure in rats. To detect the expression of insulin signaling and insulin like growth factor signaling pathway genes and the switch to fetal phenomenon.Methods: 40 Wistar rats were randomly divided into two groups(n = 20 in each group). HF group was induced by abdominal aortic banding surgery and control group was under sham surgery. After 24 weeks, all rats were tested by ultrasound to exam heart function. Fasting blood glucose and serum insulin levels were also determined. Then finish the OGTT, IVGTT, IPITT, IRT to detect the glucose metabolism and insulin sensitivity. Another 20 fetal hearts were harvested. q RT-PCR measure the expression of total insulin receptor, insulin receptor isoforms A and B,insulin receptor substrate-1,2,3, IGF-IR, GLUT-1,4 in the left ventricular tissue of fetal, normal and hypertrophy myocardium.Result: The heart function of HF group decreased significantly with severe myocardial hypertrophy. The exogenous glucose usage during OGTT and IVGTT and insulin sensitivity during IPITT were also decreased(all P<0.05). More insulin secretion were ovserved during IRT in HF group(P<0.01). m RNA of Total IR and IR-A,B, insulin receptor substrate-2,3, GLUT-1 downgrade in LV and IR, IRS-2,3expression switch to fetal.Conclusion: CHF can make disorders of glucose metabolism and induce insulin resistance and downgrade insulin signaling gene expression in heart. |
