补充L-精氨酸对热应激小鼠血清NO、NOS和T细胞亚群的影响

EFFECT OF L-ARGININE ON SERUM NO,NOS AND THYMUS T CELLS SUBSETS UNDER HEAT STRESS IN MICE

目的：通过补充不同剂量的L-精氨酸（L-Arg），探讨热应激后L-Arg对免疫功能的影响。方法：雄性成年NIH小鼠随机分为三组（A组：灌蒸馏水；B组：给L-Arg 1．5mg／gbw；C组：给L-Arg2．5mg／gbw），每组各有6只为常温对照（不经过热应激处理），另36只为热应激后分6个时间点取样。给L-Arg14d后放入动物高温仓进行热应激，干球温度（41±0．5）℃，湿球温度（33．5±0．5）℃，相对湿度65％处理120min。结束后分别取样检测血清No含量、Nos活性及胸腺T细胞亚群的变化。结果：常温下补充L-Arg组小鼠血清NO浓度、NOS活性及CD3^＋、CD4^＋细胞百分率、CD4^＋／CD8^＋比值均高于未补充组；而热应激后小鼠血清NO浓度、NOS活性、CD3^＋、CD4^＋细胞百分率、CD4^＋／CD8^＋比值补充组均明显高于未补充组，但CD8^＋细胞百分率则是补充组低于未补充组，而补充L-Arg的两组间无显著性差异。结论：热应激后4～8h小鼠免疫功能受损最严重。补充适量L-Arg可促进热应激小鼠NOS活性，提高体内NO水平，增加T细胞亚群数量及CD4^＋／CD8^＋比值。

Objective： To study the effect of arginine cells in mice under heat stress. Method： NIH-mice were （Arg） on serum NO, NOS activities and thymus T randomly divided into 3 groups and given water L-Arg 1.5 mg/g bw and L-Arg 2.5 mg/g bw for 14 d respectively. There were 42 mice in each group and were under heat stress （41 ±0.5）℃ for 120 min except 6 mice not stressed as control. Blood was taken at 0, 2, 4, 8, 12, 24 h after heat stress from 6 mice each time. The quantity of NO, activities of NOS and the change of thymus T cells in serum were measured. Results： At normal temperature or under heat stress, the quantity of NO, activities of NOS, the concentration of CD3^＋, CD4^＋ cells and CD4^＋/CD8^＋ of the groups with L-Arg were higher than those of the groups without L-Arg, but the concentration of CD8^＋ was contrary. The difference between two groups with L-Arg was not significant. Conclusion： The immunity of mice was destroyed under heat stress for 4- 8 h. The quantity of NO, activities of NOS, and the number of T cells and CD4^＋/CD8^＋in serum could be improved after given L-Arg.