添加rhGH与Gln的肠外营养对短肠大鼠代谢效应的影响

目的研究添加人重组生长激素(rhGH)及谷氨酰胺(Gln)的肠外营养(PN)对短肠大鼠机体合成代谢的作用及作用机制. 方法将SD大鼠按2×2析因设计方案随机分成STD、Gln、rhGH及GG 4组,建立PN短肠大鼠动物模型.测定各组大鼠体重及氮平衡变化,测定PN后大鼠各组织器官重量及机体总体水、脂肪及蛋白含量变化,测定血GH及IGF-1浓度. 结果 rhGH组及GG组大鼠体重显著增加,氮平衡改善;腓肠肌重量增加;机体总体蛋白明显升高,体脂下降;血GH及IGF-1显著升高,P值均<0.05;单位长度小肠重量在Gln与rhGH组显著增加,GG组增加最为明显,P<0.05. 结论 rhGH具有显著的促机体合成代谢作用,Gln作用不明显,但二者对残余小肠代偿具有协同促进作用.IGF-1在rhGH的促合成代谢机制中起重要介导作用.

The anabolic effects of recombinant human growth hormone and glutamine enriched parenteral nutrition in short bowel rats

Objective To study the anabolic effects and the underlying mechanism of recombinant human growth hormone (rhGH) and glutamine (Gln) in parenterally fed short bowel rats. Methods Rats underwent 75% small intestine resection were fed parenterally with rhGH and/or Gln for 6 days.They were weighted daily,their daily nitrogen balance (NB) and accumulated NB were calculated.After PN,organs in rats were dissected and weighted,the carcasses were used for analysis of body composition.Serum GH and IGF-1 were determined by RIA method. Results At the end of PN,rats in rhGH and GG groups weighed significantly more than those in other two groups, P <0.05.The average daily NB and accumulated NB were higher,the absolute weight of gastrocnemius muscle was increased,serum GH and IGF-1 concentration were also increased significantly, P <0.05.The weight/length of the remnant small intestine segments was higher in Gln and rhGH groups,and was highest in GG group, P <0.05.Analyses of body carcass composition showed that a higher percentage of carcass weight as protein and a lower percentage of carcass weight as fat were occurred in rhGH and GG groups, P <0.05. Conclusions rhGH significantly improved the anabolism in the parenterally fed short bowel rats.In contrast,Gln didn't improve the anabolism significantly,but both of them had synergistic effects on the increase of weight/length in remnant small intestine.IGF-1 played an important part in growth-promoting effects of rhGH.