Objective:To examine the changes of the renal tissue structure and the expression changes of hepatocyte growth factor(HGF) in the renal tissue of neonatal rats exposed to hyperoxia. Methods: Neonatal rat lung injury model was induced by exposing to hyperoxia.Seventy-two neonatal sprague-dawley(SD)rats were randomly divided into groupⅠ(n=36) and groupⅡ(n=36) within 12 h after birth. The rats in group Ⅰwere exposed to normal air while those in groupⅡ to hyperoxia. Eight rats in each group were killed on 3th

7th

14th d after birth to make the samples. The changes of the renal tissue structure were examined by hematoxylin-eosin (HE) staining method;the protein expressions of HGF in the renal tissue were detected by immunohistochemical method;the mRNA expression intensities of HGF were measured by reverse transcription polymerase chain reaction (RT-PCR). Results: ①Mesangial cell proliferation

renal tubular epithelial cells swelling and inflammatory cells infiltration were observed in group Ⅱcompared with those in groupⅠ.The pathological changes became more and more obvious with the passage of time.②The protein expression levels of HGF were enhanced on 3th d in groupⅡ compared with those in groupⅠ (P<0.05)

with more enhanced effect on 7th and on 14th d(P<0.05). However

the enhanced tendency on 14th d was weaker than that on 7th d. ③HGF mRNA expression intensities were similar to the changing tendency of their protein expression levels. Conclusion:The expression levels of HGF are enhanced in hyperoxia induced renal tissue injury.