L-精氨酸对脂多糖刺激断奶仔猪肠黏膜免疫屏障的影响

本试验旨在研究L-精氨酸(L-Arg)对脂多糖(LPS)刺激仔猪肠黏膜免疫的影响。选用24头21日龄断奶仔猪,随机分为4个处理,即对照组(基础日粮)、LPS组(基础日粮+LPS)、0.5%Arg组(基础日粮添加0.5%Arg+LPS)、1.0%Arg组(基础日粮添加1.0%Arg+LPS)。结果表明:LPS刺激损伤小肠黏膜结构;Arg则有效阻止LPS应激导致的肠道损伤,维持肠黏膜结构的完整性;LPS刺激显著增加仔猪小肠肥大细胞数(P<0.01);1.0%Arg则减少肥大细胞数(P<0.05);LPS刺激降低回肠IgA分泌细胞、CD4+、CD8+阳性细胞数(P<0.05),而0.5%Arg则增加IgA分泌细胞、CD4+、CD8+阳性细胞数(P<0.05)。这表明LPS刺激可导致仔猪小肠黏膜结构受损,免疫屏障功能降低,而日粮添加精氨酸可有效阻止LPS对肠黏膜屏障的损伤,促进及改善肠黏膜结构及免疫屏障功能。

Effect of Arginine on Intestinal Mucosal Immune Barrier in Piglets with Lipopolysaccharide Challenge

The objective of this study was to evaluate the effects of arginine(Arg) supplementation on intestinal mucosal immune barrier in piglets with lipopolysaccharide challenge.Twenty-four pigs were allotted to four treatments including: nonchallenged control(control);challenged control(LPS);0.5% [as-fed basis] Arginine(LPS + 0.5%Arg);1.0% [as-fed basis] Arginine(LPS + 1.0% Arg).On d 16 of the trial,pigs in the LPS,LPS + 0.5%Arg,and LPS + 1.0%Arg groups were challenged by injection with Escherichia coli LPS,whereas pigs in the control group were injected with sterilized saline.At 48 h post-challenge,all pigs were killed for evaluation of small intestinal morphology and immune barrier.In jejunum,and ileum,LPS caused villous LPS caused villous atrophy and intestinal morphology disruption,whereas Arg mitigated villus atrophy and intestinal morphology impairment after LPS challenge.Arg prevented the elevation of mast cell numbers induced by LPS challenge.LPS decreased the numbers of immunoglobin A-positive cells,CD4+ and CD8+ positive cells in ileum.However,0.5% Arg increased the numbers of those cells in ileum.These results indicate that Arg enhance mucosal immune barrier function and maintained normal intestinal integrity,and/or possibly via modulating intestinal inflammatory immune response.