体外循环中调节血小板功能对大鼠全身炎性反应及肺氧合功能的影响

摘要

目的:探讨体外循环(ECC)中调节血小板功能对大鼠全身炎性反应及肺氧合功能的影响.方法:将参与ECC模型的大鼠随机分为ECC中补充血小板组(MH组)、ECC中补充血浆组(MP组)和持续泵入替罗非班(Tirofiban)+ECC中补充血小板组(TMH组),每组8只大鼠.3组大鼠ECC持续2 h,术后观察2 h.采用酶联免疫吸附法(ELISA)检测3组大鼠血浆及肺泡灌洗液中炎性因子,测量氧合指数、肺组织含水量,采用流式细胞术测定循环内皮数量,苏木精-伊红染色病理学观察大鼠肺组织病理改变.分析调节血小板功能对ECC大鼠全身炎性反应水平、血管内皮损伤程度、肺组织水肿程度和肺氧合功能的影响.结果:ECC后2 h,MH组与MP组大鼠血小板数量比较差异无统计学意义(P>0.05),TMH组大鼠明显高于MH、MP组大鼠(P<0.05).ECC后2 h,3组大鼠氧合指数低于ECC开始时(P<0.05),3组大鼠肺组织含水量比较差异均无统计学意义(P>0.05),MH组大鼠支气管肺泡灌洗液中性粒细胞弹性蛋白酶(NE)水平低于TMH组大鼠(P<0.05),TMH组大鼠血浆中NE水平明显低于MP组大鼠(P<0.05).ECC结束时,3组大鼠循环内皮数量比较差异均无统计学意义(P>0.05).肺组织病理学检查提示MH组大鼠肺间质较其他各组薄,炎性细胞浸润少.结论:在ECC早期血小板急剧减少后立即补充新鲜血小板能明显减轻循环中的炎性反应,该保护效应可能与血小板黏附于ECC相关炎性反应所致的内皮损伤处并减少中性粒细胞与内皮下组织黏附有关.提示在ECC中保持一定数目且具有正常黏附聚集功能的血小板,可能降低ECC术后炎性反应和肺损伤,改善预后.%Objective:To investigate the effect of regulating platelet function on systemic inflammatory response and pulmonary oxygenation function in rats during extracorporeal circulation(ECC).Methods:The rats participating in the ECC model were randomly divided into ECC supplemented platelet group (group MH),ECC supplemented plasma group (group MP),and continuous pump Tirofiban+ECC supplemented platelet group (group TMH),with 8 rats in each group.Rats of the three groups lasted two hours with ECC,observed for two hours after operation.Enzyme linked immunosorbent assay (ELISA) was used to detect inflammatory factors in the plasma and bronchoalveolar lavage fluid of rats in the three groups.The oxygenation index and lung tissue water content were meas-ured.The number of circulating endothelial quantity was measured by flow cytometry,and pathological changes of lung tissue in rats were observed by hematoxylin eosin staining.The effects of regulating platelet function on the levels of systemic inflammatory response, the degree of vascular endothelial damage,the edema degree of lung tissue and pulmonary oxygenation function of ECC rats were analyzed.Results:There was no significant difference in platelet count between group MH and group MP after two hours with ECC(P>0.05),the group TMH was significantly higher than that in group MH and group MP (P<0.05).After two hours with ECC,the oxygenation indexes of the three groups were lower than that at the beginning of ECC(P<0.05).There was no significant difference in lung tissue water content between the three groups(P>0.05);the level of neutrophil elastase(NE) in bronchoalveolar lavage fluid of rats in group MH was lower than that in group TMH(P<0.05),the level of NE in plasma of group TMH was lower than that in group MP (P<0.05).At the end of ECC,there were no statistically significant differences in circulating endothelial quantity of the three groups (P>0.05).Pathological examination of lung tissue showed that the lung interstitium of group MH was thinner than that of other groups,and inflammatory cell infiltration was less.Conclusion:At the early stage of ECC,supplement fresh platelets after platelet sharp decrease can significantly reduce the inflammatory response in the circulation.The protective effect may be related to platelets adhere to the endothelium associated with ECC related inflammatory reactions,and decrease the neutrophils and endothelial tissue adhesion.It is suggested that certain number of platelets with normal adhesion and aggregation function in ECC may reduce inflammatory response and lung injury after operative,and improve prognosis.