【摘要】 目的动态观察患儿在体外循环(extracorporeal circulation,ECC)各时段外周血中性粒细胞(polymorphonu-clear neutrophil,PMN)的凋亡率,及其脂肪酸合成酶(Fas)、B细胞淋巴瘤(Bcl-2)蛋白表达的变化规律,为临床从PMN凋亡调控入手防治ECC引发的全身炎性反应(SIRS)提供实验室依据。方法选择择期ECC下行室间隔缺损修补术的患儿30例,采用流式细胞术检测ECC前(T0),ECC开始后30 min(T1),停ECC后30min(T2),术后24 h(T3)各时点静脉血中PMN的凋亡率、Fas和Bcl-2的表达。结果与T0比较,PMN凋亡率在T2达最低值(P<0.05),与ECC持续时间呈负相关(r=-0.648,P<0.05);与T0比较,PMN膜上Fas阳性表达百分数在T2时点降低(P<0.05),与PMN凋亡率呈正相关(r=0.546,P<0.05);与T0比较,T1、T2、T3时点PMN胞内Bcl-2阳性表达百分数升高(P<0.05),与PMN凋亡率呈负相关(r=-0.569,P<0.05)。结论小儿ECC触发全身炎性反应的过程中产生的多种凋亡抑制因素使PMN凋亡受到抑制,其机制与PMN的Fas表达下调和Bcl-2表达上调有关。更多还原

【Abstract】 OBJECTIVE To investigate the changes in polymorphonuclear neutrophil(PMN) apoptosis and Fas,Bcl-2 protein expression of pediatric patients undergoing open-heart surgery with ECC,and to give the experimental basis for treating systemic inflammatory reaction syndrome(SIRS).METHODS Thirty pediatric patients with ventricular septal defect undergoing open-heart surgery with ECC were studied.Blood samples were taken after induction of anesthesia(T0),30 minutes after the initiation ECC(T1),30 minutes after the termination ECC(T2) and 24 hours post-operatively(T3).PMN apoptosis and the expression of PMN Fas,Bcl-2 protein were detected by flow cytometry.RESULTS Compared with T0,the rate of PMN apoptosis reached to its lowest value at T2(P<0.05).The percentage of PMN apoptosis correlated negatively with the duration of ECC(r=-0.648,P<0.05).Fas on PMN membrane at T2 was significantly downregulated than T0.Fas levels correlated positively with PMN apoptosis rate(r=0.546,P<0.05).PMN intracellular expression of Bcl-2 at T1,T2,T3 was significantly upregulated than T0(P<0.05).Bcl-2 levels correlated negatively with PMN apoptosis rate(r=-0.569,P<0.05).CONCLUSION The PMN apoptosis can be delayed by ECC.The inhibition of PMN apoptosis has relation with the down regulation expression of Fas and the upregulation expression of Bcl2.更多还原