川芎嗪对缺氧模型大鼠脑干谷氨酸脱羧酶的影响

Effect of Tetramethlpyrazine on GAD Expression in Brainstem of Hypoxia Rats

目的探讨川芎嗪(tetramethlpyrazine,TMP)对缺氧大鼠呼吸中枢的保护作用,以及该作用与脑干谷氨酸脱羧酶(GAD)蛋白的关系。方法将健康成年SD大鼠24只随机分为4组,空气对照组和单纯TMP各4只,单纯缺氧组和缺氧加TMP组各8只。空气对照组大鼠气管套管侧管通入空气;单纯缺氧组气管套管侧管通入相同流量低氧气体;缺氧加TMP组气管内通入低氧气体,麻醉前30min和缺氧前30min分别腹腔注射20g.L-1TMP注射液,80mg.kg-1;单纯TMP组除气管内通入相同流量空气外,其余同缺氧加TMP组。免疫组化方法检测各组大鼠脑干神经元GAD蛋白表达情况。结果空气对照组、单纯TMP对照组、单纯缺氧组和缺氧加TMP组大鼠脑干均有GAD阳性表达神经元,阳性表达神经元主要分布于HN、LRN、疑核(ambiguousnucleus,Amb)、前包钦格复合体(pre-Botzingercomplex,PBC)、FN和TZ。与空气对照组及单纯TMP对照组比较,单纯缺氧组和缺氧加TMP组灰度值明显降低,阳性神经元个数明显升高(P<0.05)。与单纯缺氧组比较,缺氧加TMP组灰度值明显升高,阳性神经元个数明显降低(P<0.05)。结论TMP能对抗缺氧所致的呼吸抑制,脑干内GAD蛋白可能参与了TMP对呼吸中枢的保护作用。

Objective To study the GAD related protective effect of tetramethlpyrazine （TMP） on the respiratory inhibition induced by hypoxia in rats brainstem. Methods The immunohistochemical technique were used to investigate the effect of hypoxia on the GAD expression in the brainstem and the antagnistie action of TMP. Results In the brainstem, GAD positive neurons were mainly existed in the HN, LRN, ambiguous nucleus （Amb）, pre-Botzinger complex （PBC）, FN and TZ. In contrast to the air control and TMP control groups, the level of GAD immunoreactivity was enhanced remarkably by hypoxia. In the rats with hypoxia plus TMP, the positive expression of GAD was obviously weaker than that in the rats with hypoxia alone （P 〈0.05）. Conclusion TMP has protective effects on the respiratory inhibition induced by hypoxia, and GAD may be involved in the process.