RESUMO
Objective To explore the role of caspase-3 activation and DNA fragmentation in later period of neonatal rat hypoxic-ischemic brain damage(HIBD). Methods DNA fragmentation,caspase-3 mRNA and caspase-3 protein were measured in 2 wks、3 wks and 4wks after setting HIBD animal model in newborn wistar rats by FCM, RT-PCR and Immunohistochemistry. Results (1) Apoptosis lasted 4ks after HIBD. This suggested a long lasting role of apoptosis in neonatal HIBD by TNNEL and EM.(2)Caspase-3 mRNA expression was estimated by semi-quantitative RT-PCR. It was higher in HIBD group(0.771?0.074) than in control group(0.620?0.038, P0.05. Average Avalue of Caspase-3 protein in HIBD group(0.374 ?0.038) at 3 wks was significantly higher than that in control group(0.356?0.020,P