局灶低温治疗大鼠创伤性脑水肿及其对钠-钾-ATP酶的影响

Role of local hypothermia on traumatic brain edema andNa^+-K^+-ATPase in brain tissue in rats

目的 观察局灶低温治疗对大鼠脑创伤后脑水肿、钠 钾 ATP酶的影响。方法 SD大鼠 84只 ,随机分成 3组 :A组 ,假手术对照组 :B组 ,脑外伤模型对照组 :C组 ,2 5°C水局灶低温治疗组。除A组外各组动物均按Feeney方法造成重度脑创伤 ,B组伤后不予治疗 ,C组伤后 30min开始给予局灶低温治疗 ,2 0～ 30min局灶脑温降至 31°C并维持 3h。各组又根据伤后观察时间长短分 1d、3d、5d、7d等四个时段亚组。所有动物分别于伤后l、3、5、7d处死 ,取伤区脑组织测水含量及钠 钾 ATP酶含量。结果 B组与A组比 ,脑组织水含量升高、钠 钾 ATP酶下降 (1、3、5、7d组均P <0 .0 5 )。C组与B组相比 ,C组水含量下降、钠 钾 ATP酶含量升高 (1、3、5、7d组均P <0 .0 5 )。结论 对大鼠脑创伤后脑水肿 ,2 5°C水局灶低温治疗有效 ,维持钠 钾 ATP酶活性可能是其作用机制之一。

Objective To investigate the effect of local hypothermia (LH) on traumatic brain edema and Na +-K +-ATPase in brain tissue.Methods 84 adult SD rats were randomly divided into three groups: group A,sham injury group; group B,TBI controlled group; group C,treated by LH with water of 25°C.All animals except group A were subjected to traumatic brain injury (TBI) with Feeney's method.LH began for animals in group C 30 minutes after TBI.Within 20～30 minutes regional brain temperature reached the target temperature of 31 °C and maintained for three hours.Each group were divided in four sub-groups by investigating duration after TBI: one day(1 d),three day(3 d),five day(5 d) or seven day(7 d) sub-group.At the end of investigating duration animal was sacrificed and water content(WC),concentration of Na +-K +-ATPase in brain tissue were measured.Result Compared with group A,WC of group B increased but Na +-K +-ATPase decreased significantly(1 d,3 d,5 d,and 7 d P<0.05).Compared with group B,WC of group C decreased but Na +-K +-ATPase increased significantly(1 d,3 d,5 d,and 7 d P<0.05).Conclusion Local hypothermia with water of 25°C had effect on traumatic brain edema.The mechanism of local hypothermia may associate with maintaining the activity of Na +-K +-ATPase.