【摘要】 目的探讨亚低温治疗及选择时机对窒息大鼠心肺复苏后的脑保护作用。方法将60只SD大鼠随机分为假手术组(A组)、常温组(B组)、保存性低温组(C组)、复苏性低温组(D组),除A组外,其余各组均建立心肺复苏大鼠模型。B、C、D组内按心跳骤停的时间(4、5.5、7 min)再分为3个亚组。C组和D组分别在心跳骤停时和自主循环恢复(ROSC)后30 min分别给予保存性低温和复苏性低温的亚低温治疗,B组不行低温治疗,A组仅进行麻醉、气管切开及血管穿刺操作,不进行心肺复苏。各组于相应时间点取血和脑组织标本,分别观察各组血清S100B蛋白含量,大脑皮层S100B蛋白表达及脑组织含水量比。结果 (1)与A组比较,B、C、D组血清S100B蛋白含量从ROSC后2 h起开始明显升高,并持续上升至4 h,各时点血清S100B蛋白含量及ROSC后4 h大脑皮层S100B蛋白表达均显著升高(P<0.05)。(2)与B组比较,C、D组ROSC后2 h血清S100B蛋白含量有所降低,但差异无统计学意义(P>0.05),ROSC后4 h血清S100B蛋白含量显著降低(P<0.05),ROSC后4 h皮层S100B蛋白表达显著降低(P<0.05)。(3)与A组比较,B、C、D组ROSC后2 h脑含水量均显著升高(P<0.05);与B组比较,C、D组ROSC后2 h脑组织含水量在数值上有所降低,但差异无统计学意义(P>0.05)。(4)与D组比较,C组ROSC后4 h血清S100B蛋白含量、大脑皮层S100B蛋白阳性细胞数,ROSC后2 h脑组织含水量仅有数值上的降低,而差异均无统计学意义(P>0.05)。结论亚低温治疗能减轻窒息大鼠心肺复苏后脑损伤,具有确切的脑保护效应,其疗效与诱导亚低温开始的时间有关。更多还原

【Abstract】 Objective To study protective effects of mild hypothermia on brain and cooling timing after cardiac arrest- cardiopulmonary resuscitation( CA- CPR) in anoxia- induced rats. Methods Sixty adult SD rats were randomly divided into 4 groups: sham- operation group( Group A),normothermia group( Group B),instant hypothermia group( Group C),and resuscitation hypothermia group( Group D); among which CA- CPR models were established except for in Group A. The subjects in CPR groups were further subdivided into 3 subgroups according to CA durations( 4,5. 5 and 7 min). Hypothermia was performed immediately and 30 min after CA in Group C and Group D,respectively. Tracheotomy,anesthesia and vascular centesis were carried out in Group A,without asphyxiation or CPR. Blood and brain samples were collected. Serum levels of S100B protein,the expression of S100B protein in cerebral cortex,and water content of brain tissue were measured. Results Compared with Group A,the serum levels of S100B protein were significantly increased 2 h after ROSC,and kept increasing until 4 h after ROSC in Group B,C and D; meanwhile,the expression of S100B protein in cerebral cortex was also significantly up- regulated 4 h after ROSC in Group B,C and D( P < 0. 05). Compared with Group B,though there was no significant reduction in serum S100B 2 h after ROSC in Group C or D( P > 0. 05); the significant reduction in serum S100B and down- regulation in S100B in cerebral cortex were observed 4 h after ROSC in Group C and D( P < 0. 05). Compared with Group A,significant increase in brain water content were observed 2 h after ROSC in Group B,C and D( P < 0. 05). However,there was no significant reduction of brain water content in Group B when comparing with Group C or D( P > 0. 05). Compared with Group D,reduction in serum S100B and expression of S100B in cerebral cortex were observed 4 h after ROSC in Group C,so was brain water content 2 h after ROSC; but there was no significant difference was revealed( P > 0. 05). Conclusion Mild hypothermia has neuroprotective effects in anoxia rats after CPR via alleviating the cerebral injury,but the effect is related of mild hypothermia timing.更多还原