低温对失血性休克炎症小体活化的影响研究

目的 探索治疗性低温对失血性休克(hemorrhagic shock,HS)大鼠肺组织炎症小体活化的影响.方法 本研究将24只SD大鼠随机(随机数字法)分成3组:假手术组,常温液体复苏(normothermia resuscitation,NR)组,低温液体复苏(hypothermia resuscitation,HR)组.各组通过股动脉放血到平均动脉压达40 mmHg(1 mmHg=0.133 kPa)保持1h建立HS模型,随后NR组和HR组通过液体复苏使平均动脉压达90 mmHg,维持1h,4h后通过放血处死各组大鼠,留取大鼠肺组织.经苏木精-伊红(HE)染色于光镜下观察肺组织的损伤程度,使用于湿比重法检测肺组织水肿情况,采用RT-PCR和Western blotting检测肺组织炎症小体NLRP-3、Caspase-1、IL-1βmRNA和蛋白表达水平.多组间比较采用方差分析,组间两两比较采用SNK-q检验,以P＜0.05为差异具有统计学意义.结果 (1) HE染色结果示,与NR组相比,HR组急性肺损伤程度明显较低.(2)肺组织湿/干比重与HR组相比NR组肺水肿显著降低,HR组(5.85 ±0.10);NR组(6.47±0.17),t=3.14,P＜0.05;(3)与NR组相比,HR组的NLRP-3和Caspase-1的蛋白表达均显著减少;(4)与NR组相比,HR组的NLRP-3 mRNA表达水平显著降低,HR组(1.027±0.143),NR组(1.349 ±0.163),t=4.36,P＜0.05;HR组的IL-1β mRNA表达水平显著降低,HR组(1.623±0.125),NR组(2.388±0.229),t=7.72,P＜0.05.结论 治疗性低温能够降低炎症小体信号通路的活化,从而减弱HS诱导的肺组织损伤.

Effect of hypothermia on the activation of inflammasome in the lung tissue during hemorrhagic shock

Objective To explore the effect of therapeutic hypothermia on the activation of inflammasome in the lung tissue of rats with hemorrhagic shock (HS).Methods Twenty-four male Sprague-Dawley rats were randomly (random number) divided into three groups:sham group,normothermia resuscitation (NR) group and hypothermia resuscitation (HR) group.Rats of each group were subjected to pressure-controlled (MAP 40 mmHg) HS for 1 h,then the NR group and the HR group were resuscitated with lactated Ringer and MAP was maintained at 90 mmHg for 1 h.Four hours later,the rats in each group were sacrificed by exsanguination.Hematoxylin eosin staining was used to observe the injury of lung tissue.The desiccation method was used to detect the edema of lung tissue.RT-PCR and western blot were employed to evaluate the mRNA and protein expression of NLRP-3,IL-1β,caspase-1.Analysis of variance was used for comparison among groups,and SNK-q test was used for comparison between two groups.Results (1) The injury of lung tissue in HR group was significantly milder than that in NR group;(2) Wet/dry (W/D) weight ratio of lung in HR group decrease compared with NR group [HR group 5.85 ± 0.102;NR group 6.471 ± 0.165 8 (t =3.14,P ＜ 0.05)];(3) NLRP-3 and of Caspase-1 protein expression in the HR group were lower than those in NR group.(4) The NLRP-3 mRNA expression in HR group was lower compared with NR group [(HR group 1.027 ± 0.143;NR group 1.3487 ± 0.163 (t =4.36,P ＜ 0.05)] and IL-1 mRNA expression in HR group was lower compared with NR group [HR group 162.3 ± 0.125;NR group 2.388 ± 0.229 (t =7.72,P ＜ 0.05)].Conclusions Therapeutic hypothermia attenuated ALI induced by HS in rats by modulation of signal way of inflammasome.