星状神经节阻滞预处理对急性缺氧大鼠海马神经元凋亡的影响

目的探讨星状神经节阻滞（SGB）预处理对急性缺氧大鼠海马神经元凋亡的影响及其作用机制。方法取健康清洁级雄性SD大鼠48只按随机数字表法分为3组：正常对照组（C组）、急性缺氧组（AH组）和星状神经节阻滞预处理＋急性缺氧组（SGB组）,每组16只。AH组和SGB组大鼠制备急性缺氧模型。SGB组于模型制备前解剖暴露右侧颈交感神经干并用布比卡因行右侧SGB,以出现霍纳综合征为SGB成功标志;AH组解剖暴露右侧颈交感神经干后注入等容量的生理盐水;C组不给予任何操作。大鼠经广口瓶取出后6h时处死取海马组织,每组随机取8只大鼠检测海马Bax和Bcl-2蛋白表达,并计算Bcl-2/Bax比值;另外8只大鼠检测海马神经元凋亡情况。结果与C组比较,AH组和SGB组海马组织Bcl-2和Bax表达上调,Bax/Bcl-2比值升高,神经元凋亡增多（P〈0.05）;与AH组比较,SGB组海马组织Bcl-2表达上调,Bax表达下调,Bax/Bcl-2比值降低,神经元凋亡减少（P〈0.05）。结论星状神经节阻滞预处理可减轻急性缺氧诱发的大鼠脑损伤,其机制可能与其抑制海马神经元凋亡有关。

Effect of Stellate Ganglion Block Preconditioning on Hippocampal Neuron Apoptosis in Rats with Acute Hypoxia

Objective To investigate the effect of stellate ganglion block（SGB）preconditioning on hippocampal neuron apoptosis and its mechanism of action in rats with acute hypoxia.Methods Forty-eight healthy male SD rats were randomly divided into three groups,with 16rats in each group.Acute hypoxia was induced in acute hypoxia group（group AH）and SGB＋acute hypoxia group（group SGB）.In group SGB,the right cervical sympathetic nerve trunk was exposed and blocked with bupivacaine before acute hypoxia and the SGB was determined by the appearance of Horner＇s syndrome.In group AH,the same amount of saline was given after the exposure of cervical sympathetic nerve trunk.Rats in group C received no treatment.Rats were sacrificed to obtain hippocampus at 6hours after they were removed from the jar.The expression of Bax and Bcl-2in hippocampus was detected in 8rats and hippocampal neuron apoptosis was determined in other 8rats in each group.Results Compared with group C,the expression of Bcl-2and Bax,Bax/Bcl-2ratio and neuron apoptosis significantly increased in group AH and group SGB（P0.05）.Compared with group AH,Bcl-2increased but Bax expression,Bax/Bcl-2ratio and neuron apoptosis decreased in group SGB（P〈0.05）.Conclusion SGB preconditioning can attenuate cerebral injury in rats with acute hypoxia through a mechanism involving the inhibition of hippocampal neuron apoptosis.