亚低温及银杏叶提取物对大鼠缺血脑组织氨基酸水平的影响

Effects of sub-hypothermia and ginkgo biloba extract on levels of amino acid in cerebral ischemia tissue of rats

目的探讨亚低温及银杏叶提取物(GBE)对大鼠缺血脑组织谷氨酸(Glu)、天门冬氨酸(Asp)和γ-氨基丁酸(GABA)水平的影响。方法 48只Wistar大鼠随机分为假手术组、脑缺血对照组、亚低温组、轻度高温GBE组、常温GBE组及亚低温GBE组,每组8只。用线栓法制作大鼠脑缺血模型,GBE组在缺血前12 h～缺血后2 h 4次腹腔注射GBE 300 mg/kg。用高效液相色谱法测定脑组织Glu、Asp、GABA含量。结果与假手术组比较,除亚低温GBE组Glu、Asp及亚低温组Asp外,其他各组缺血脑组织Glu、Asp、GABA水平均显著增高(P<0.05～0.001)。与脑缺血对照组比较,常温GBE组、亚低温组及亚低温GBE组缺血脑组织Glu、Asp水平均显著降低(均P<0.001),GABA水平均显著增高(P<0.01～0.001)。与常温GBE组比较,亚低温组及亚低温GBE组缺血脑组织Glu、Asp水平和轻度高温GBE组缺血脑组织GABA水平均显著降低(P<0.01～0.001);而亚低温组及亚低温GBE组缺血脑组织GABA水平和轻度高温GBE组缺血脑组织Glu、Asp水平均显著增高(P<0.01～0.001)。亚低温组与亚低温GBE组缺血脑组织Glu、Asp、GABA水平差异无统计学意义。结论亚低温和GBE都能降低缺血脑组织Glu、Asp水平,使GABA水平升高,两者联合应用效果更好。

Objective To investigate the effects of the sub-hypothermia and ginkgo biloba extract（GBE） on the levels of Glutamate（Glu）,aspartate（Asp） and γ-aminobutyric acid（GABA） in cerebral ischemia tissue of rats.Methods 48 Wistar rats were randomly divided into sham operated group,cerebral ischemia control group,sub-hypothermia group,GBE with mild high temperature group,GBE with normal temperature group and GBE with sub-hypothermia group.There were 8 rats in each group.The model of cerebral ischemia rat was established by intraluminal suture method.300 mg/kg GBE was intraperitoneal injected 4 times from 12 h before ischemia to 2 h after ischemia.The concentrations of Glu,Asp and GABA in cerebral ischemia tissue of rats were detected by high performance liquid chromatography（HPLC）.Results Compared with the sham operated group,the levels of Glu,Asp and GABA were significantly increased in all ischemia groups（P〈0.05～0.001） except the levels of Glu and Asp in GBE with sub-hypothermia group and the level of Asp in sub-hypothermia group.Compared with the cerebral ischemia control group,the levels of Glu and Asp were significantly decreased（all P〈0.001） and the level of GABA was significantly increased（P〈0.01～0.001） in GBE with normal temperature group,sub-hypothermia group and GBE with sub-hypothermia group.Compared with the GBE with normal temperature group,the levels of Glu,Asp in sub-hypothermia group and GBE with sub-hypothermia group and the level of GABA in GBE with mild high temperature group were significantly decreased（P〈0.01～0.001）;while thr level of GABA in sub-hypothermia group and GBE with sub-hypothermia group and the levels of Glu,Asp in GBE with mild high temperature group were significantly increased（P〈0.01～0.001）.There was no statistical significance on the levels of Glu,Asp and GABA between sub-hypothermia group and GBE with sub-hypothermia group.Conclusion Both sub-hypothermia and GBE can decrease the levels of Glu,Asp and increase the level of GABA in cerebral ischemia tissue.And it results better when sub-hypothermia combined with GBE.