本试验旨在研究十二指肠灌注亮氨酸（leucine，Leu）对山羊胰腺外分泌及血浆指标的影响，进而为提高反刍动物小肠淀粉利用率提供理论依据。本研究采用4×4拉丁方试验设计，选用4只周岁龄关中奶山羊，手术安装十二指肠瘘管、总胆管插管，进行十二指肠Leu灌注试验（灌注水平分别为0、3、6、9 g/d），研究Leu不同灌注水平对胰腺外分泌功能、血浆葡萄糖及胰岛素浓度的影响。结果表明：十二指肠灌注Leu，血浆中的葡萄糖和胰岛素含量、胰液分泌量、胰液总蛋白质浓度及合成速率、胰蛋白酶、糜蛋白酶和脂肪酶的分泌均不受影响（P＞0.05）。随Leu灌注水平的提高，胰腺α-淀粉酶的分泌浓度差异不显著（P＞0.05），而分泌速率呈先升高后降低再回升的变化规律（P<0.05）。结果提示，Leu可不依赖于胰岛素直接长期调控山羊胰腺α-淀粉酶的分泌。
The experiment was conducted to investigate the effect of duodenal infusion of leucine (Leu) on pancreatic exocrine secretion and plasma indices in goats. Four one-year-old goats [(30.1±1.3) kg] fitted with duodenal fistulas and common bile duct cannulas were used in a 4×4 Latin square design. Each goat received four treatments: infusion of 0, 3, 6 and 9 g/d Leu into duodenum, respectively. The results showed that duodenal infusion of Leu didn’t affect concentrations of glucose and insulin in plasma, total pancreatic juice secretion, total protein concentration and production rate in pancreatic juice, and activities of trypsin, chymotrypsin, lipase and pancreatic α-amylase (P＞0.05). However, the secretion rate of pancreatic α-amylase was increased when the infusion level of Leu was 3 or 9 g/d (P<0.05). The results indicate that Leu can directly long-term regulate the secretion of pancreatic α-amylase independent of insulin in goats.［Chinese Journal of Animal Nutrition, 2011, 23（9）：1513 -1518］
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