内毒素血症磷脂酶A2的激活与细胞膜流动性的变化

采用大肠杆菌内毒素休克兔实验模型，研究了红细胞膜磷脂酶Ａ２（ＰＬＡ２）活性，膜荧光偏振度的各向异性系数的变化。内毒素组注射内毒素后各时相点平均动脉压显著低于对照组（Ｐ〈０．０１），ＰＬＡ２活性显著高于对照组（Ｐ〈０．０１），膜荧光偏振度、各向异性系数亦显著高于对照组（Ｐ〈０．０１）。药物预处理组上述变化较小，与内毒素组相比差别显著（Ｐ〈０．０５）。结果表明：内毒素致ＰＬＡ２活性升高，并由此导致膜微

PHOSPHOLIPASE A2 ACTIVATION AND MEMBRANE FLUIDITY ALTERATION IN ENDO-TOXIMIA

In order to gain insight into the mechanism on cell impairment and the effect of phospholipase A2 (PLA2) inhibitors during endotoxic shock,we investigated the PLA2 activity,fluorescence polarization and anisotrophy of erythrocytic membranes on the rabbits with endotoxic shock.It was revealed that the survial rate during the 8 h experimental period was l00%,58%,87.5%and 75%respectively. Mean arterial blood pressure in endotoximia period group dropped remarkablly following endotoxin infusion compaired with that in control one (P<0.01).PLA2 activity rised significantly with the depression of membrane fluidity in endotoximia group.A mild alteration was found in Chloroquine or Chlorpromazing pretreatment group.The resuIts indicated that PLA2 activity elevated obviously during endotoxic shock from which the alteration of membrane microenvironment and dysfunction resulted.PLA2 inhibitors were found to lessen PLA2 activity,abate cellular dysfunction and improve survival rate,which may provide a valuable experimental evidence for the clinic use in endotoximia and septic shock.