Effect of EGF on expression of EGFR and EGF mRNA in the injuried lung tissue of neonatal premature rats exposed to hyperoxia / 中国病理生理杂志

ABSTRACT

AIM:To investigate the effect of exogenous epidermal growth factor(EGF) on expression of EGFR and EGF mRNA of the injuried lung tissue of neonatal premature rats exposed to hyperoxia.METHODS:The neonatal Sprague-Dawley rats of 21-day gestational age model of hyperoxia induced lung injury were made by continually inhaling 95% oxygen.The model rats were divided into two groups randomly,the EGF trail group and the NS control group.The other rats were taken into the air control group.Each group was divided into three subsetsa(1-3 days),b(4-6 days) and c(1-6 days) according to different application times of EGF or NS.Rats in sub groups were executed and the lung tissues were removed at postnatal 3th,7th,14th day respectively.Using immunohistochemistry method,the expression of EGF-R of lung tissues in different groups was observed,and the expression of EGF mRNA was determined by reverse transcriptase polymerase chain reaction(RT-PCR).RESULTS:The expression of EGF mRNA increased by degrees following the increasing postnatal days.Compared with the air control group,the expression of EGF-R and EGF mRNA increased in the hyperxia group at 7th day and 14th day.The expression of EGF-R increased in corresponding hyperxia NS control group at 14th day(P