The Effects Of 17β-estradiol On Cerebrocellular Apoptosis In The CA1 Pyramidal Cell Layer Of HIBD Ratu

Obiective:To study the effects of 17β-estradiol on cerebrocellular apoptosis of poxic-ischemic brain damage(HIBD) in neonatal rats,and on Serum sFas/sFasL level in braintissue.Methods:Select 7-day old newborn Wistar rats to establish HIE model,and intraperitoneatly and subcutaneous injected17β-estradiol,then the rats were killed after hypoxia and ischemia for another 48 hours.The number of cerebrocellular apoptosis of rats were detected after the brain tissue were stained by HE and TUNEL.For parts of rats, Concentration of sFas and sFasL in femoral venous blood was measured by ELISA.Results:(1)Few neuronal apoptosis was detected in SO group.Apoptosis of neurons in CAl region was observed at 6h after HIBD and increased obviously at 24h(P＜0.01)and then decreased at 72h,which was still higher than that in SO group(P＜0.01).In the intervention group,the number of apoptotic neurons was much fewer than that in HIBD group,especially in 24h(P＜0.01).(2) Concentration of sFas and sFasL in femoral venous blood increased obviously at 24h after HIBD(P＜0.05),and then decreased at 72h,which was still higher than that in SO group(P＜0.05).In the intervention group,concentration of sFas and sFasL was much lower than that in control group,especially in 48h(P＜0.01).Conclusions:(1) The expression of neuronal apoptosis in CAl region increased obviously after hypoxic-ischemia brain damage.However neuronal apoptosis in intervention group decreased significantly.It suggested that 17β-estradiol could partly inhibit neuronal apoptosis to protect neurons and attenuated brain injury after HIBD in neonatal rats.(2) The concentration of sFas in control group was significantly higher than that SO group.And the concentration of sFas in the intervention group was lower than that of control group.