重组人生长激素对烧伤大鼠肠道细菌／内毒素移位的影响

Effect of recombinant human growth hormone on intestinal bacteria/endotoxin translocation in rats with burns

目的观察早期应用重组人生长激素(recombinant human growth hormone,rhGH)对严重烧伤大鼠肠道细菌/内毒素移位的影响。方法30只成年雄性Wistar大鼠随机分为对照组、烧伤组和rhGH 3组。后2组造成25%总体表面积(TBSA)Ⅲ度烫伤,立即腹腔注射地塞米松80 mg/kg,伤后2 h分别给予等渗盐水和rhGH 1.33 IU/kg。伤后8、24 h,观察肠道细菌移位频率、门静脉与腔静脉血清内毒素含量、腔静脉血清肿瘤坏死因子(TNF)α含量和肝功能变化。结果rhGH组肠道细菌移位频率和组织细菌含量均明显低于烧伤组(P<0.05),与对照组比较差异无统计学意义(P>0.05);rhGH组门、腔静脉内毒素含量明显低于烧伤组(P<0.01);腔静脉TNFα含量和肝功能指标明显低于烧伤组(P<0.01,P<0.05)。结论早期应用大剂量rhGH能有效减轻严重烧伤后肠道细菌/内毒素移位,减少炎性介质释放,保护脏器功能。

Objective To investigate the effects of recombinant human growth hormone （rhGH） on intestinal bacteria/endotoxin translocation in early severely burned rats. Methods 30 adult male Wistar rats were randomly divided into three groups： the control group, the burn group and the rhGH treatment group. Rats in the burn and the rhGH treatment groups were inflicted with 25% total body surface area （TBSA） full-thickness skin ,scald on their backs immediately followed by intraperitoneal injection of dexamethasone （80 mg/kg）, then they were subcutaneously subjected to normal saline and rhGH （1.33 IU/kg） 2 hours after burning. Changes of the intestinal bacteria translocation rate, the endotoxin level in the portal and cava veins, the level of tumor necrosis factor （TNF）α in the cava venous serum and hepatic function were determined 8 and 24 hours after burning. Results The intestinal bacteria translocation rate and the bacterial level in the rhGH group were significantly lower than those of the burn group （ P 〈 0.05）, but were not significantly different from those of the control group （ P 〉 0.05）. The endotoxin level in the rat portal and cava veins of the rhGH group was also significantly lower than that of the burn group （ P 〈 0.01 ）. The level of TNFα in the cava vein and the indexes of hepatic function of the rhGH group were markedly lower than those of the bum group （ P 〈 0. 01, 0. 05）. Conclusion A high dose of rhGH administered at an early stage following burning could effectively reduce intestinal bacteria/endotoxin translocation, decrease the release of inffammatory mediators and protect hepatic function.