氯胺酮对全脑缺血大鼠的脑保护作用

The neuroprotection of ketamine in a model of transient forebrain cerebral ischemia rats

目的探讨氯胺酮对全脑缺血大鼠的脑保护作用。方法健康成年SD大鼠30只,随机均分为缺血加氯胺酮组(A组)、缺血组(B组)、假手术组(C组)。以Pulsinelli-Brierley方法为标准建立四动脉阻断法全脑缺血模型,A、B组行全脑缺血15min后再灌注,其中A组于全脑缺血5min时腹腔给氯胺酮100mg/kg,B组相同时间腹腔内注射同体积生理盐水,C组分离椎动脉及颈总动脉后不行全脑缺血。再灌注3d后经心脏灌注固定后取脑制作石蜡切片,分别行HE染色观察海马CA1区神经元存活数目和TUNEL法检测海马CA1区神经元凋亡。结果C组大鼠海马CA1区神经元大部分存活,少量神经元凋亡;B组神经元很少存活,大量凋亡,细胞计数明显少于C组(P<0.01);A组神经元存活数目明显少于C组,但多于B组(P<0.01),凋亡数目明显多于C组,但少于B组(P<0.01)。结论氯胺酮对脑缺血大鼠具有一定的脑保护作用。

Objective To investigate the neuroprotection of ketamine in a model of cerebral ischemia rats. Methods Thirty adult healthy SD rats were randomly divided into three groups with 10 rats each. The global cerebral ischemia model was produced by four-vessel occlusion for 15 min as described by Pusinelli-Brierley in group A and B. The rats in group C were not suffered from forebrain cerebral ischemia after bilateral vertebral arteries and common carotid arteries seperated. The rats of group A were injected with ketamine 100 mg/kg into peritoneal cavity 5 min after cerebral ischemia,while the rats of group B were treated with the same volume physiologic saline at the same time. The survived neurons in the CA1 sector of the hippocampus were observed with histopathological technique, meanwhile the neurones apoptosis in the CA1 sector hippocampus was detected by TUNEL method 3 days after cerebral reperfusion. Results There were a lot of neurons survived and a few TUNEL-positive cells observed in group C. Meanwhile the survived neurons were more and TUNEL-positive cells were less in group A than those in group B （P〈0.01）. But the survived neurons were less and TUNEL-positive cells were more in group A than those in group C （P〈0.01）. Conclusion Ketamine has a certain neuroprotective effect on ischemic rats.