Valsartan After Balloon Injury Of Rat Aortic Endothelial Angiotensin-converting Enzyme 2 Expression

Aim:To investigate the process of intimal thickening, expression of angiotensin-coverting enzyme 2 (ACE2), angiotensin-coverting enzyme (ACE) and the effects of Valsartan on them after vascular balloon injury in rats.Methods:Rat models of aortic endothelial denudation were made by an 2F balloon catheter. Rats were randomly allocated into three groups:Group 1 served as controls. Group 2 were given vascular balloon injury. Group 3 were given Valsartan (20mg/kg/d) from 1day before injury to 30 days after injury.The expression of ACE mRNA, the level of protein of ACE2 and ACE were investigated at day 14 and 30 after injury by reverse transcription polymerse chain reaction (RT-PCR) technique and immunohistochemistry method, respectively.Results:Intimal thickening was significant at 14 days and 30 days after injury Valsartan significantly and comparably prevented intimal thickening at 14 days and 28 days after balloon injury. The expression of ACE mRNA and protein was significantly increased at 14 days and 30 days after injury (p<0.05), while the expression of ACE2 protein was significantly increased at 14 days and 30 days after injury (p<0.05). Valsartan can not only increase the expression of ACE2 protein (p <0.05) but also decrease the expression of ACE mRNA and protein.Conclusions:①The expression of ACE2 protein decreased and the expression of ACE increased after balloon injury.②Valsartan can increased the expression of ACE2 protein, but decreased the expression of ACE.③The effects of Valsartan on aortic endothelial denudation and regression of vascular remodeling are related with the increased expression of ACE2 protein and the decreased expression of ACE.