高压氧对缺氧缺血性脑损伤新生大鼠caspase-3及caspase-9表达的影响

Effect of hyperbaric oxygen-treatment on the expression of caspase-3 and caspase-9 in the newborn rats brain of hypoxic-ischemia

目的:通过检测caspase-3,caspase-9的表达情况,探讨高压氧(HBO)对缺氧缺血新生大鼠脑细胞凋亡的影响及分子机制.方法:建立缺氧缺血性脑损伤(HIBD)大鼠模型,将其分为HIBD组(24只)及HBO干预组(24只),同时设立假手术(Sham)组(24只).分别于造模后18,24,48和96h4个时间点断头取脑观察其病理改变(海马及皮层区),并用免疫组化的方法检测caspase-3及caspase-9的蛋白表达.结果:HIBD组18,24,48和96h时间点海马及皮层区caspase-3,caspase-9蛋白的表达均明显高于Sham组(P<0.05),HBO干预组则显著缓解,caspase-3,caspase-9表达的升高程度均低于HIBD组(P<0.05).结论:HBO能减轻新生大鼠HIBD模型海马及皮层区脑细胞的凋亡,其作用可能是通过下调caspase-9进而影响caspase-3的活性表达来完成的.

AIM： To explore the effect of Hyperbaric Oxygen （HBO） on the apoptosis resulted from Hypoxic-Ischemic Brain Damage（HIBD）, and to observe the change of Caspase-3 and Caspase-9 expression in this process. METHODS： The hypoxiaischemia models were divided into following 3 groups： HIBD model group （ 24 cases ）, HBO treatment group （ 24 cases） and sham operation group （24 cases）. The brain were taken from the model at 18, 24, 48 and 96 h after the model was made by decapitation. Then observe the morphologic change of brain tissues（the hippocampus and the cortex） and check the dynastic change of Caspase-3 and Caspase-9 expression by immunohistochemistry at different time points. RESULTS： The expression of Caspase-3 and Caspase-9 in the hippocampus and cortex was higher than that of sham group at 18, 24, 48 and 96 h time point. Compared with HIBD（P 〈0.05）. The increased rate of Caspase- 3 and Caspase-9 expression was significantly decreased at each time point by HBO treatment（ P 〈 0.05 ）. CONCLUSION ： HBO decreased the apoptosis of hippocampus and cortex nerve cells on 7-day-old HIBD rat model. It is suggested that through downregulation of Caspase-9 and decrease of the expression of Caspase- 3, HBO treatment prevent brain cells from apoptosis.