浅低温联合尼莫地平静脉输注对兔全脑缺血-再灌注损伤IL-1、TNF-α、IL-10表达的影响

Effect of sub-hypothermia combined with nimodipine infusion on the global cerebral ischemic-reperfusion injury in rabbit

目的探讨浅低温(32～33℃)联合尼莫地平静脉输注对兔全脑缺血-再灌注损伤的保护机制。方法健康新西兰大耳白兔40只,随机均分为五组。采用双侧颈总动脉夹闭低血压脑缺血模型,除正常对照组(V组)外,Ⅰ、Ⅱ、Ⅲ、Ⅳ组均行脑缺血30min,再灌注3h;Ⅱ组在双侧颈总动脉夹闭的同时行局部脑组织浅低温处理,Ⅲ组则在夹闭同时静脉输注尼莫地平10μg·kg-1.h-1,Ⅳ组则同时采取局部脑组织浅低温和静脉输注尼莫地平10μg·kg-1.h-1,上述处理均维持至再灌注后3h。常规监测鼓膜温度、MAP、CVP,分别于缺血前(T0)、缺血后30min(T1)、再灌注30min(T2)、1h(T3)、2h(T4)、3h(T5)采血标本,再灌注3h后处死动物,以干湿重比测定脑水含量。酶联免疫吸附法(ELISA)检测血清白细胞介素(IL)-1、肿瘤坏死因子α(TNF-α)、IL-10的表达。结果脑水含量Ⅰ组明显高于其他四组(P<0.05),其他四组之间差异无统计学意义。与T0时比较,Ⅰ组血清IL-1表达在T1时升高,T4时达高峰(P<0.05或P<0.01),TNF-α表达在T1时升高并达高峰(P<0.01)。Ⅱ～Ⅳ组血清IL-1、TNF-α表达在T1时升高(P<0.01),Ⅰ组血清IL-1、TNF-α表达T2～T5时明显高于Ⅱ～Ⅴ组(P<0.01)。Ⅱ组IL-1、TNF-α表达T2～T4时略高于Ⅳ、Ⅴ组,但低于Ⅰ组(P<0.01)。Ⅰ组IL-10表达在T1时开始下降,T5时达最低,与Ⅰ组相比,Ⅱ～Ⅳ组分别经浅低温、尼莫地平处理后T2时血清IL-10表达升高,并持续至T5(P<0.01)。结论浅低温及浅低温联合尼莫地平静脉输注能显著减少血清IL-1、TNF-α表达,增加IL-10表达,减轻兔全脑缺血-再灌注损伤的炎性反应。

Objective To investigate the effect of sub-hypothermial combined with nimodipine infusion on the expression of interllukine（IL）-1, tumor necrosis factor α（TNF-α） and IL-10 in plasma after the global cerebral ischemic/reperfusion（I/R） injury. Methods Forty healthy New Zealand rabbits were randomly divided into five groups. The model was made by occluding the bilateral common carotid arteries for 30 min combined with hypotension. Except normal group （group V）, groups of Ⅰ , Ⅱ , Ⅲ, Ⅳ were ischemic for 30 min and reperfused for 3 hours, local cerebral sub- hypothermia was given to group Ⅱ for 3 hours combined with the same I/R, 10 μg·kg^-1·h^-1 nimodipine was infused in group Ⅲ during ischemic treatment, and the sub-hypotherrnia combined with nimodipine infusion was given in group Ⅳ. The temperature, MAP and CVP were recorded and the arterial blood was taken before ischemia, at 30 min after ischemia, reperfusion for 30 min, 1,2 and 3 hours. ELISA method was used to detect the IL-1, TNF-α, IL-10 expression in plasma. Results The water contant of the brain was significantly high in group Ⅰ, but the difference was not significant among the other four groups. The expression of IL-1 was increased at T1 and reached peak at T4, but the TNF-α was increased and reached peak at T1 in group Ⅰ , compared with T0, the difference was very significant （P〈0. 01）. The expressions of IL-1 and TNF-α were increased in T1 in group Ⅱ to Ⅳ （P〈0. 01）. The level was significantly higher in group Ⅰ than that in groups of Ⅱ, Ⅲ, Ⅳ, Ⅴ at T2 to T5 （P〈0.01）. In group Ⅱ ,the levels of the IL-1 and TNF-α were little more than group Ⅳ, Ⅴ at T2 to T4 ,but lower than those in group Ⅰ （P〈0. 01）. The expression of IL-10 was decreased at T1 and the lowest at T5 in group Ⅰ , after the sub-hypothermia and/or nimodipine infusion in groups of Ⅱ , Ⅲ, Ⅳ, the expression of IL-10 was increased at T2 and maintained until at T5, compared with group Ⅰ , the difference was significant （P〈 0.01 ）. Conclusion The sub-hypothermia and sub- hypothermia combined with nimodipine infusion can reduce the expressions of IL-1 and TNF-α and increase the expression of IL-10 significantly, indicating that it may attenuate the inflammation response after global I/R injury in rabbits.