Different concentrations of insulin affect the growth and proliferation of in vitro cultured cardiomyocytes from neonatal rats / 中国组织工程研究

ABSTRACT

BACKGROUND:Study on mouse models of hyperinsulinemia confirms that hyperinsulinemia can induce the occurrence of myocardial hypertrophy. OBJECTIVE:To study the effect of insulin on proliferation and hypertrophy of cardiomyocytes in neonatal mice in vitro cultured. DESIGN,TIME AND SETTING:The in vitro cytology experiment was performed at the Key Laboratory of Anatomy,Histology and Embryology of Xinxiang Medical University from January 2006 to March 2007. MATERIALS:Twenty Wistar neonatal mice aged 1-3 days were used in this study. Insulin was obtained from Sigma,USA. METHODS:Cardiomyocytes of neonatal mice were in vitro harvested,culture and purified by trypsin digestion and differential attachment technique. Cardiomyocytes were incubated in 10-8,10-7,10-6 mol/L insulin for 48 hours. Blank control group was set up. 10-7 mol/L insulin group was used for cell cycle analysis. MAIN OUTCOME MEASURES:Cell diameter,activity and counting were measured under a microscope. The expression of cyclin E in cardiomyocytes was measured using immunocytochemistry. RESULTS:Cardiomyocyte activity in each group was over 90%. Compared with the blank control group,long diameter and short diameter of cardiomyocytes in the 10-8,10-7,10-6 mol/L insulin groups were significantly increased(t=2.781 5,P 0.05) ,but the number of cardiomyocytes in the 10-6 mol/L insulin group significantly decreased(t=1.976 2,P