The effects of estrogen on hypoxic pulmonary vascular remodeling

Objective To observe the effects of 17 β estradiol (E 2 ) on hypoxic pulmonary vascular remodeling.Methods Twenty four male SD rats were randomly divided into four groups:control group,hypoxic group,E 2 preventive group,and E 2 treatment group.The animal model of hypoxic pulmonary hypertension was established by regular exposing the rats to normabaric hypoxic conditions for 3 weeks.The mean pulmonary artery pressure (mPAP) and right ventricle hypertrophy index were examined.Lung speciments were examined by light microscopes and morphometric analysis.The WT% (ratio of vascular wall thickness to vascular external diameter) and WA% (ratio of vascular wall area to total vascular area) were measured by a computerized image analyzer.E 2 in blood serum was measured by radioimmunoassay.Results (1)In the hypoxic group,mPAP,RV/(LV+S),WT% and WA% were increased significantly compared with those in the control group ( P 0 01).However,E 2 level in the serum in the hypoxic rats was not significantly different from that in the control rats( P 0 05).(2)In the preventive and treatment groups,mPAP,RV/(LV+S),WT%,and WA% decreased remarkably as compared with those in the hypoxic group,respectively ( P 0 05).E 2 levels in the serum in the preventive and treatment groups were higher than that in the hypoxic group ( P 0 01).Conclusion 17 β estradiol may have the preventive and therapeutic effects on the hypoxic pulmonary vascular remodeling.