丙酮酸乙酯对烫伤延迟复苏大鼠细胞免疫功能的影响

Effects of ethyl pyruvate on cell - mediated immune function in rats with delayed resuscitation after burn Injury

目的观察丙酮酸乙酯(EP)对烫伤延迟复苏大鼠细胞免疫功能的影响,并探讨其作用机制.方法采用大鼠30%总体表面积Ⅲ度烫伤模型,103只大鼠随机分为正常对照组(n=7)、假烫伤组(n=32)、烫伤组(n=32,伤后6 h腹腔内注入40 ml/kg生理盐水)和EP(3.23 mg/ml)干预组(n=32,伤后6 h腹腔内注入40 ml/kg EP液),分别于伤后1、3、5和7 d活杀,检测脾淋巴细胞增殖能力、白细胞介素-2(IL-2)生成及白细胞介素-2受体(IL-2R)表达.结果烫伤延迟复苏后1～7 d,脾淋巴细胞丝裂原刺激的增殖反应明显受抑制(P均<0.05).烫伤后1～5 d IL-2生成明显减少(P均<0.05),且烫伤后1和3 d IL-2R的表达显著降低(P均<0.05).EP干预能够明显恢复烫伤后1～7 d脾淋巴细胞的增殖能力(P均<0.05),伤后1、3和5 d,IL-2的生成显著增加,但对IL-2R的表达无影响(P均>0.05).结论 EP能显著增加脾淋巴细胞的增殖能力和IL-2的产生,从而有效改善烫伤延迟复苏后细胞免疫功能障碍.

Objective To investigate the effects of ethyl pyruvate (EP) on cell - mediated immune function in rats with delayed resuscitation after burn injury, and its potential regulatory mechanism. Methods Wistar rats were subjected to 30% full -thickness scald injury with delayed resuscitation. One hundred and three male rats were randomly divided into normal controls (n = 7), sham scald group (n = 32). scald group (n = 32) in which 40 ml/kg normal saline was infused peritoneally 6 hours after scald, and EP treatment group (n = 32) in which 40 mg/kg EP was injected peritoneally 6 hours after scald. Animals were sacrificed on postburn day 1, 3, 5. and 7, and spleen was collected to determine splenocyte proliferation, IL - 2 production and cell -surface IL - 2 receptor (IL - 2R) expression. Results Splenic lymphocyte proliferation responses to T cell mitogen, concanavalin A (Con A), were depressed from 1 to 7 days after scald injury (all P<0. 05). Meanwhile, in comparison with sham scald group, burn injury resulted in a significant decrease in splenic production of IL - 2 on postburn day 1, 3, as well as 5, and a marked suppression of IL - 2R expression on days 1 and 3 postburn (all P<0. 05). Treatment with EP after burn injury showed a dramatic restoration of lymphocyte proliferation rate and increased production of IL - 2 at various time points (all P<0. 05). However, treatment with EP did not affect IL - 2R expression compared with scalded rats (all P>0. 05). Conclusion Treatment with EP could markedly elevate splenic T lymphocyte proliferation response and increase production of IL - 2 following burn injury, thereby improving cell - mediated immunity in thermally injured rats with delayed resuscitation.