Expression and Effects of p53 in Pulmonary of Rats After 21 days' Hypoxia and Pulmonary Vascular Remodeling

Objective To investigate the expression of mutated p53 in pulmonary of rats after 21 days' hypoxia,and investigate the cause of pulmonary vascular remodeling(PVR) in hypoxic pulmonary hypertension(HPH) rats.Methods 20 healthy Spraque-Dawley male rats were randomly divided into two groups: control group(n=10),hypoxic group(n=10).Then the model of hypoxic pulmonary hypertension were established by exposing rats to normobaric hypoxic conditions for 8 hours one day in 3 weeks continually except rats of control group.At first,mean pulmonary arterial pressure(mPAP) was measured by a right cardiac catheterization.Then,right ventricular hypertrophy was represented as the ratio of right ventricular weight to left ventricular weight plus septum weight [RV.(LV+S)-1].Leica Qwin Image Analyzer was used to measure the vascular morphologic indexes of pulmonary in rats:(MA%),(MT%) and(VA%).Immunohistochemical staining Method(SP) was used to examine the expression of p53 in paraffin-embedded specimens of rats pulmonary tissue.Results After 21 days' hypoxia,mPAP,RV.(LV+S)-1,MT%,VA% and expression of p53 in hypoxic group increased obviously higher than control group(P0.01orP0.05),VA% decreased higher than control group(P0.01).Conclusion Expression of mutated p53 gene was obviously increased,and expression of wild gene p53 was possibly decreased in pulmonary of rats after 21 days’ hypoxia,which resulted in enhancing cell proliferation and decreasing apoptosis,then improved the development of PVR and HPH finally.