失血性休克再灌注后血浆内皮素的变化及磷脂酶A_2阻断剂对它的影响

家兔出血性休克再灌注（Ｓ／Ｒ）后，放免分析发现血浆内皮素逐渐升高，同失血前比较第６ｈ有显著差异（Ｐ＜０．０５），假手术组没有改变。磷脂酶Ａ_２阻断剂氯喹、磷酸萘酚喹和抗氧化剂黄芪酮于失血后再灌注前使用可抑制Ｓ／Ｒ后２ｈ内血浆内皮素增高，后两者可更明显降低Ｓ／Ｒ后３０ｍｉｎ的内皮索水平，与失血前比较差异非常好著（Ｐ＜０．０１）。同时，ＨＣＯ~－_３和碱贮备（ＳＢＣ）显著降低，上述三种药物治疗显著增加ＨＣＯ~－_３和ＳＢＣ的含量，它们在Ｓ／Ｒ后２４ｈ明显高于Ｓ／Ｒ组的水平（Ｐ＜０．０１）。结果提示，Ｓ／Ｒ后血浆内皮素上升可能与代谢性酸中毒加重有一定联系。磷脂酶Ａ_２阻断剂和抗氧化剂可能通过早期抑制内皮素的释放，从而减轻２４ｈ后代谢性酸中毒程度。

Changes of Plasma Endothelin and Effect of Phospholipase A_2 Inhibitor on Its Alteration after Hemorrhagic Shock/Reperfusion

Plasma endothelin (ET) was gradually increased and significantly higher than that of pre-shock period at 6h after hemorrhage/reperfusion (S/R) in rabbit,while sham group had no changes. Furthermore,ET was decreased in 2h after S/R injury by the use of phospholipase A2 inhibitor chloroquine,ME8101 and antioxidant (TFA) during shock period,and in particular,ME810l and TFA markedly reduced ET level within 30min after S/R,which was significantly lower than that of pre-shock period ( P <0. 01 ). Meanwhile,plasma HCO3- and SBC increased at 24h after S/R by the administration of these agents, being significantly higher than that of S/R group ( P <0. 01 ). The results indicated that the increase of ET after S/R appears to be related with the advance of acidosis,and phospholipase A2 inhibitor and antioxidant could be used to block ET release,and to improve acidosis induced by the S/R injuries.