维拉帕米、牛磺酸抑制烧伤休克延迟复苏大鼠心肌组织的PLA_2活性

Inhibitions of PLA_2 activities by verapamil and taurine in myocardium of burned rats after delayed resuscitation

目的：研究烧伤休克延迟复苏对心肌组织磷脂酶Ａ２（ＰＬＡ２）活性的影响以及维拉帕米、牛磺酸的抑制作用。方法：雄性ＳＤ大鼠造成３０％体表面积的Ⅲ度烧伤，分为烧伤不复苏（Ｂ）组、早期复苏（ＢＥ）组、延迟复苏（ＢＤ）组、延迟复苏＋维拉帕米（ＢＤＶ）组和延迟复苏＋牛磺酸（ＢＤＴ）组，伤后８ｈ取左心室肌组织匀浆后用盐酸滴定法测定ＰＬＡ２活性。结果：Ｂ组心肌组织ＰＬＡ２活性非常明显高于正常对照（Ｃ）组（Ｐ＜０．０１）；ＢＤ组酶活性显著高于ＢＥ组和Ｂ组（Ｐ＜０．０５）；ＢＤＶ、ＢＤＴ组酶活性显著低于ＢＤ组（Ｐ＜０．０５）。结论：烧伤休克延迟复苏可进一步激活心肌组织ＰＬＡ２活性，维拉帕米、牛磺酸抑制ＰＬＡ２活性可能是拮抗心肌缺血再灌注损伤的机制之一。

Objective: To study the effects of delayed resuscitation on the activities of PLA_2 in myocardium of severely burned rats and inhibitory roles of verapamil and taurine. Methods: Male SD rats were inflicted to 30%TBSA, full-thickness burn injury, and were classified to serve as burn with no fluid resuscitation (B) group, burn with early fluid resuscitation (BE) group, burn with delayed resuscitation (BD) group, burn with delayed resuscitation plus verapamil(BDV) and taurine(BDT) group. Gathered at 8 h postburn, the left ventricular myocardium PLA_2 activities were assayed by HCl titration after homogenation. Results: The activities of PLA_2 were very significantly higher (P<0.01) in B group compared with normal control group, and in BD group compared with BE group. Furthermore, the activities were significantly higher (P<0.05) in BD group compared with B group. Verapamil and taurine could significantly inhibit the PLA2 activities in delayed resuscitation groups (P<0.05). Conclusion: Delayed resuscitations of burn shock most severely stimulate the PLA2 in myocardium, resulting in the ischemiareperfusion injuries. Verapamil and taurine might have protection roles against the ischemiareperfusion injuries through inhibiting the PLA_2.