The effect of arginine supplementation on intestinal growth and absorption after massive small bowel resection in growing rats

*目的*我们研究了补充精氨酸(Arg)对生长期大鼠大量小肠切除后肠道生长和吸收的影响。材料和方法4周龄雄性SD大鼠接受了90%的小肠切除。术后第4天开始，随机分为实验1组和实验2组，分别给予基础饲料(0.8kcal/ml，50ml/d)和等氮等能补充精氨酸或L-甘氨酸，喂养3周和6周。分别于术后3周和6周进行比较。统计分析采用非配对学生检验和单因素方差分析(ANOVA)，采用Bonferroni/Dunn多重比较检验。结果两组患者术后3周的进食量、体重、尾长、剩余回肠长度和血浆C/IGF-I水平无显著差异。而第1组的回肠绒毛高度和第6周的回肠长度分别显著高于第2组和第2组。生长激素释放激素激发试验(每只大鼠静脉注射1杯)显示，补充精氨酸(Arg)组的生长激素(GH)分泌在5min时比补充甘氨酸(Gly)组显著升高。两组大鼠血浆GH基础水平差异无统计学意义。血浆Cit水平通过补充Arg而改变，而Arg水平在3周时通过大量小肠切除和补充Arg而改变。而6周时两组间血浆Cit和Arg水平无明显差异。2组大鼠术后6周肾组织学检查显示肾小管间质纤维化。结论Arg对大鼠小肠切除后GH分泌、肠道生长和改善吸收能力可能具有重要作用。

*Purpose* We studied effects of arginine (Arg) supplementation on intestinal growth and absorption after massive small bowel resection in growing rats.*Material and Methods* Four-week-old male Sprague-Dawley rats underwent a 90% small bowel resection. From the fourth day after surgery, they were divided into group 1 and 2, and pair-fed by elemental diets (0.8 kcal/ml, 50 ml/day) withL-arginine or L-glycine as an isonitrogenous and isoenergetic supplement for 3 and 6weeks. They were compared with each other at 3 and 6 weeks after surgery. A statistical analysis was performed using the unpaired Student's test and the one-way factorial analysis of variance (ANOVA) using Bonferroni/Dunn multiple comparison test. AP-value of <.05 was considered significant.*Results* There were no significant differeces between the two groups in food intake, body weight, tail length, remaining ileal length, and plasma somatomedin C/IGF-I level at 3 weeks after surgery. However, the mean height of ileal villi at 3 weeks and remaining ileal length at 6 weeks in group 1 showed significantly higher and longer than those in group 2, respectively. Growth hormone-releasing hormone provocative tests (1 mug per rat, intravenously) showed the more significant elevation of growth hormone (GH) secretion in the Arg supplement group than that of glycine (Gly) supplement group at 5 minutes. There were no significant differences between basal levels of plasma rat GH in both groups. Plasma Cit level is changed by Arg supplementation, and Arg level is changed by massive small bowel resection and Arg supplementation at 3 weeks. However, there were no differnces of plasma levels of Cit and Arg between the two groups at 6 weeks. Histological study of the kidney showed tubulointerstitial fibrosis in group 2 at 6 weeks after surgery.*Conclusion* It is suggested that Arg has a possible significant role of GH secretion, intestinal growth and improving absorptive capacity after massive small bowel resection.