缺氧缺血新生鼠脑caspase-3活性的变化

目的 了解缺氧缺血对新生鼠脑组织caspase-3活性的影响并探讨其意义。方法 7d龄Wistar大鼠分为假手术组、缺氧缺血脑损伤(HIBD)组。HIBD组新生鼠行左颈总动脉结扎后，吸入氧氮混合气(氧浓度为8％)1L／min持续2h。于1、12、24、48h取脑组织在低温下进行匀浆，离心后取上清用四肽荧光底物法测定其荧光强度。结果 HIBD后1h caspase-3活性已升高，24h达高峰，48h明显下降。各时间点左侧脑组织荧光强度之间比较，差异有显著性；各时间点与假手术组比较，左侧脑组织荧光强度差异有显著性。结论 HIBD新生鼠脑组织中caspase-3明显激活。可能为临床新生儿缺氧缺血性脑病(HIE)脑损伤的重要原因。

Activity of caspase-3 in cerebral tissue of the neonatal hypox ic ischemic rat

Objective To study the effect of hypoxia ischemia on caspase 3 activity in cerebral tissue of neonatal rats and its significance Methods Wistar rats of 7 d were divided into sham operation group and HIBD(Hypoxic ischemic brain damage) group In HIBD group, the left carotid artery of rats was ligated and animals were exposed to 8% oxygen for 2 h At 1, 12, 24, and 48 h after HIBD, both ipsilateral and contralateral cerebral tissues were homogenized and centrifugated Caspase 3 activity was measured by cleavage of the fluorescence substrate AC DEVD AMC Results Caspase 3 activity in ipsilateral cerebral tissue increased gradually after HIBD and peaked at 24 h, and then decreased significantly at 48 h Compared with that of the control, Caspase 3 activity significantly changed in the ipsilateral tissue at all time points Conclusion The obviously activated caspase 3 in neonatal cerebral tissue in HIBD groups may be the important factor leading to hypoxic ischemic encephalopathy(HIE) of the newborn