局部亚低温对大鼠脑出血后血肿周围脑组织白介素-1β表达的影响

Effects of local sub-hypothermia on expression of interleukin-1β in brain tissue of perihematoma following intracerebral hemorrhage in rats

目的观察局部亚低温对脑出血大鼠血肿周围脑组织的形态学变化和对白介素(IL)-1β表达的影响。方法72只Wistar大鼠随机分为假手术组和脑出血后6h、24h、48h、72h、7d组,每组再分为常温亚组和亚低温亚组,每个亚组6只大鼠。采用自体不凝血注入大鼠尾状核制备脑出血模型。各亚低温亚组注血后实施亚低温治疗4h,维持脑温在(33±0.5)℃。观察血肿周围组织的形态学改变和IL-1β表达的变化。结果亚低温亚组各时间点脑组织水肿明显轻于常温亚组;神经元变性坏死、炎症反应及胶质细胞增生程度明显轻于常温亚组。脑出血后6h血肿周围脑组织IL-1β开始表达,48h达高峰,7d时仍明显高于对照亚组(均P<0.01)。脑出血24h～7d亚低温亚组IL-1β表达水平较相应时点常温亚组显著降低(均P<0.01)。结论亚低温治疗能明显抑制血肿周围IL-1β的过度表达,减轻血肿周围脑组织的炎症反应。

Objective To investigate the effects of local sub-hypothermia on the changes of histomorphology and the expression of interleukin（IL）-1β in brain tissue of perihematoma following intracerebral hemorrhage（ICH）in rats.Methods 72 Wistar rats were randomly divided into sham-operation group,ICH 6 h group,ICH 24 h group,ICH 72 h group and ICH 7 d group;each group was divided again into normothermia sub-group and sub-hypothermia sub-group,and 6 rats in each sub-group.Rat ICH models were established by autologous blood injection.The rats in sub-hypothermia sub-group were given local sub-hypothermia therapy immediately after the injection,and keep the intracerebral temperature at 32.5℃ to 33.5℃ for 4 h.Then,the changes of histomorphology and the expression of IL-1β in brain tissue of perihematoma were observed.Results The brain tissue edema,neuronal degeneration,inflammatory reaction and colloid cellular proliferation were more serious in normothermia sub-group than in sub-hypothermia sub-group at every time point after ICH.The expression of IL-1β was increased at 6 h of ICH,peaked at 48 h of ICH and higher than control subgroup until 7 d of ICH（all P0.01）.The expression of IL-1β in sub-hypothermia sub-groups of ICH 24 h^7 d were significantly lower than those in corresponding normothermia sub-group（all P0.01）.Conclusion Sub-hypothermia therapy can significantly inhibit overexpression of IL-1β and relieve the inflammatory reaction in brain tissue of perihematoma.