氯胺酮对不完全性脑缺血的保护作用

Protective effects of ketamin on incomplete cerebral ischemia

目的：观察氯胺酮对兔不完全性脑缺血后神经损害后果的影响，并探讨其可能的作用机制。方法：１２只家兔随机分为两组。缺血对照组（组Ⅰ，只数＝６），氯胺酮组（组Ⅱ，只数＝６），组Ⅱ用氯胺酮２５ｍｇ／ｋｇ静脉注射和５０ｍｇ／ｋｇ肌肉注射作前处理。采不同时相动脉血分别测定血浆ＴＮＦ、ＮＡ、Ａ的水平。结果：缺血３０分钟组Ⅱ血浆ＴＮＦ、ＮＡ、Ａ浓度显著低于组Ⅰ（Ｐ＜０．０５），神经损害的后果及与卒中有关的死亡率，组Ⅱ也较组Ⅰ明显改善。结论：用氯胺酮前处理可以明显改善不完全性兔脑缺血的神经学损害，其机制可能与氯胺酮拮抗缺血期中枢ＮＭＤＡ受体和抑制外周儿茶酚胺释放，降低ＴＮＦ水平有关。

Objective:The effects of ketamine on outcome from incomplete cerebral ischemia in rabbits were observed Method:Twelve rabbits were randomly divided into two groups:ischemia control group (Ⅰ,n=6),ketamine group (Ⅱ,n=6),with pretreatment of ketamine 25 mg/kg I V and 50 mg/kg I M For measurement of level plasma NA,A,TNF at different interval,arterial samples were collected Results:In group Ⅱ,plasma NA,A,TNF levels were lower than group Ⅰ at 30 min ischemia (P<0 05),neurologic outcome and stroke related mortality were improved,compare with group Ⅰ (P<0 05).Conclusion:The pretreatment with ketamine may improve singnificantly outcome from incomplete cerebral ischemia The action mechanisms are probably related to its NMDA receptor antigonism, the inhabition of catecholamine release and decrease of plasma TNF level during ischemia