头部重点低温脱水综合疗法脑复苏机制的研究(对激动性氨基酸变化的影响)

为检测头部重点低温脱水综合疗法（ＳＨＣＤＣＴ）能否消除激动性氨基酸神经毒性，观察了完 全性脑缺血（四血管式，３０分钟）后再灌注 ３０、１８０和 ３６０分钟（ｎ＝８）时颞叶组织中谷氨酸（Ｇｌｕ）、门冬氨 酸（Ａｓｐ）含水量和葡萄糖等的变化，比较了头部重点低温（ＳＨＣ，２８℃，体表降温法）、甘露醇脱水和 ＳＨＣＤＣＴ三种治疗对这些变化的影响。发现与未缺血动物相比，再灌注后Ａｓｐ、Ｇｌｕ和含水量升高（Ｐ＜ ０．０１ ），葡萄糖减少（Ｐ＜０． ０１），ＳＨＣ和 ＳＨＣＤＣＴ显著抑制这些变化（Ｐ＜０． ０１），促进它们尽快恢复到未 缺血水平。结果提示：再灌注后尽早实施ＳＨＣＤＣＴ仍能有效缓解激动性氨基酸神经毒性，这可能是 ＳＨＣＤＣＴ脑复苏机制之一。

Experimental study of mechanism of selective head cooling-dehydration combined therapy for brain resuscitation: effects on levels of excitatory amino acids.

In order ic assess the effects of selective head cooling--dehydration combined therapy (SHCDCT)on the excitoxicities of excitatory amino acids (EAA),one hundred and four New Zealand rabbits,aged 3 to 4 months,served as the experimental subjects. Eight of them acted as the normal control(groupl),and after having underwent the complete cerebral ischemia for 30 mins,which was induced by tying off the branchiocephalic trunk,the left subclavicular artery and both internal thoracic arteries, the 96 subjects left were divided randomly into four groups:group and . The brains of the subjects in each of these later four groups were reperfused respectively for 30, 180 and 360 mins. The subjects in group were regarded as model control,in group received the intravenous injection of mannitol 1. 6g. kg--1every three hours at one minute following the reperfusion,in group were given the intravenous lyticcocktail to be adjunct to the head surface cooling at the same time as the reperfusion,and in group v were treated with the combination of the above both ways. After the required procedures were completed,the samples of temperol cerebral tissuses were taken,in which the amounts of aspartic acid (ASP)and glutamic acid (GLU)were determined with liquid chromatography,the water content was calculated by the Elliot equation,and the glucose level and the activity of creatine phosphokinase enzyme (CPK)were measured with biochemical methods. As compared with the normal control levels in group ,the amounts of GLU,ASP And water and the activity of CPK increased markedly,and the glucose content decreased significantly in group (P<0. 05). In comparison with the model control levels in group E,the amounts of GLU and water decreased drastically in group and (P<0. 05),the levels of ASP and the activity of CPK reduced remarkably,but one of glucose rose obviously in group and (P<0. 05 ),and the three levels kept statistically stable in group . The degrees of the improvements of all above parameters were highed in group v than those in group . It is suggested that SHCDCT may be effective for the cerebral resuscitation by attenuating the excitoxicities of excitatory amino acids.