局灶性脑缺血大鼠脑组织硫化氢水平的动态变化

Dynamic changes of content of hydrogensulfide in brain tissue of focal cerebral ischemia of rats

目的观察大鼠局灶性脑缺血过程中不同时间内源性H2S含量的变化。方法健康成年雄性SpragueDawley（SD）大鼠共192只,体重250~300 g,随机分为假手术组、缺血1h组、缺血3h组,缺血6h组,缺血9h组,缺血12h组,缺血24h组。假手术组共48只（不同时间点各8只）,其余组各8只。其中96只观察计算梗死体积,另96只测定其他指标。采用Zea-Longa线栓法建立局灶性脑缺血模型,参照Longa评分法,对大鼠进行神经功能缺损程度的评分,于术后1、3、6、9、12和24h后断头取脑,观察并计算脑梗死体积,检测脑组织中H2S水平。结果与假手术组比较,缺血1h组无明显变化,从缺血3h到24h,出现不同程度的神经功能缺损症状,随着时间的延长,缺血3、6、9、12和24 h时梗死灶增大（P〈0.01）,各组大鼠脑组织中H2S水平均明显降低（P〈0.05或〈0.01）。结论缺血3h后,随缺血时间延长,脑组织梗死体积逐渐增大,H2S含量明显降低。

Objective To observe the changes of content of endogenous hydrogensulfide（ H2S） during different time points in brain tissue of focal cerebral ischemia of rats. Methods One hundred and ninety-two male Sprague-Dawley（ SD）rats weighted 250 ~ 300 g were randomly divided into seven groups： sham-operation group,ischemia 1h,3h,6h,9h,12 h,24h group,with 96 rats in sham-operation group and 16 rats in each ischemia group. Among 192 rats,the infarction area in 96 rats were detected,however,the other parameters were detected in the other 96 rats. The focal cerebral ischemia models in rats were established by Zea-Longa thread ligation,then according to Longa scoring method,the neurologic impairment degree scoring was performed. The cerebral infarction area was calculated by means of image analysis system at 1h,3h,6h,9h,12h,24h after operation and the levels of H2S in brain tissue were detected. Results As compared with those in sham-operation group,the symptoms of neurological impairment were more and more obvious from 3h to 24h after ligation,with the time going on,the cerebral infarction area was gradually increased from 3h to 24h（ P〈0. 01）. Furthermore the levels of H2S in brain tissue were significantly decreased in ischemia 3h,6h,9h,12 h and 24 h groups,as compared with those in sham-operation group（ P〈0. 05 or P〈0. 01）. Conclusion With time going on,the cerebral infarction area in rats is gradually increased from 3h to 24h after ischemia and the contents of H2S were obviously decreased,which suggests that H2S may play an important role during physiopathologic process of focal cerebral ischemia.