Programming About Cardiovascular Rennin Angiotensin System Of Offspring Rats From Hypoxia During Pregnancy

Objective To study the influence of chronic hypoxia during pregnancy oncardiovascular rennin angiotensin system programming in male offspring rats.Methods Chronic hypoxia models in different periods of pregnancy were established.36pregnant rats were randomly assigned to six groups as follows: hypoxia groupsstarted in pregnancy on the third day (G1),6thday (G2),9thday (G3),12thday (G4),15thday (G5) and control group (G0). Each group contained six animals. The changesof RAS components in the heart and the aorta tissue of male offspring rats at the12thweeks and the20thweeks of age were detected in each group, to make a preliminaryanalysis of the correlation between the RAS in the heart and the aorta tissue andchronic hypoxia during pregnancy.Results Chronic hypoxia during pregnancy could activate the cardiovascularACE-AngII-AT1axis in adult male offspring rats by changing the mRNA and proteinexpression of ACE and AT1receptors or the generation of AngII(all P<0.05). Chronichypoxia during pregnancy could change the mRNA and protein expression of ACE2,AT2receptors and Mas receptors or the generation of Ang-(1-7)(all P<0.05) andactivate the cardiaovascular ACE2-Ang-(1-7)-Mas axis in male offspring rats. ThemRNA and protein expression of ACE、ACE2、AT1R、AT2R were significantly higherin G1、G2and G3group than G0group(all P<0.05), and the G1group was also themost obvious. Some of them showed significant difference between G4and G0groups，and showed significant difference between G5and G0groups.Conclusions Hypoxia during pregnancy in rats could lead to the generation of AngIIand Ang-(1-7), expression of ACE, ACE2, AT1, AT2and Mas receptors andprogramming about ACE-AngII-AT1axis and ACE2-Ang-(1-7)-Mas axis incardiovascular rennin angiotensin system of male offspring rats. All these changes aremost obviously observed in the adult male offspring rats of hypoxia group started inpregnancy on the third day (G1), which indicates that the more and earlier exposure ofhypoxia during pregnancy may have more obvious effects on offspring rats.