目的:研究在不同模式的低氧训练过程中小肠免疫功能的应激反应和适应性变化规律及其机制。方法:5周龄雄性SD大鼠90只,随机分为:常氧对照(NC,n=10)组、常氧运动训练(NE,n=20)组、低氧对照(HC,n=20)组、低氧+运动训练(HE,n=20)组和高住低训(LHTL,n=20)组。通过人工低氧和游泳训练模拟高原训练和高住低训,分别在2周和6周后测定小肠组织中分泌型免疫球蛋A(SIgA)、防御素-5(RD-5)、溶菌酶、白细胞介素4(IL-4)、转化生长因子-β(TGF-β)含量以及多聚免疫球蛋白受体(p Ig R)和J链m RNA的表达。结果:(1)2周的运动训练使大鼠小肠组织中SIgA、溶菌酶、IL-4和TGF-β含量显著性降低,低氧暴露使SIgA、RD-5、溶菌酶、IL-4和TGF-β含量以及J链、p Ig R m RNA表达显著性降低,在低氧条件下进行运动训练对进一步降低SIgA、RD-5、溶菌酶、IL-4和TGF-β含量具有显著性的交互作用。(2)6周的运动训练使RD-5、溶菌酶、IL-4和TGF-β含量显著性降低,低氧暴露也可使SIgA、RD-5、溶菌酶、IL-4和TGF-β含量显著性降低,在低氧条件下进行运动训练对进一步降低RD-5、溶菌酶、IL-4和TGF-β含量具有显著性的交互作用,但对进一步降低SIgA含量、J链和p Ig R m RNA的表达无显著性的交互作用。(3)与NC组相比,2周的LHTL组溶菌酶、IL-4和TGF-β含量显著性降低,6周的LHTL组TGF-β含量显著性降低。与HE组相比,2周的LHTL组SIgA、RD-5、溶菌酶、LI-4和TGF-β含量有所增加,但无显著性差异,而J链和p Ig R的m RNA表达极显著性增加;6周的LHTH组SIgA、RD-5、溶菌酶、IL-4、TGF-β含量和p Ig R m RNA表达均显著性增加。结论:(1)低氧暴露和大强度的运动训练均可抑制肠道粘膜的免疫功能,在低氧条件下进行运动训练比单纯的低氧或者运动训练对肠道免疫功能的损伤更为严重。在低氧和运动这两个因素中,低氧暴露?
Objective The purpose of the study is to training on the immune function of small intestine. explore the effects of different modes of hypoxic Methods The contents of intestinal secretory immunoglobulin A (SIgA), rat defensins-5 (RD-5), lysozyme, interleukin-4 (IL-4), transforming growth factor- β(TGF-β),polyimmunoglobulin receptor (pIgR), and J chain plgR mRNA expression of rats were measured at the 2nd and 6th week of simulated altitude training or living in high altitude and training in low altitude (LHTL). Results (1)The contents of intestinal SIgA,lysozyme,IL-4,TGF-β,and the expressions of J chain and pIgR mRNA reduced significantly 2 weeks after the hypoxic training. There was significant interaction of hypoxic training to the further reduction of the contents of intestinal SIgA, lysozyme, IL-4 and TGF-β. (2)The content of RD-5,1ysozyme,IL-4 and TGF-β reduced significantly after 6 weeks of hypoxic training or exposure to hypoxic environment. There was significant interaction of hypoxic training to the further reduction of the contents of RD-5, lysozyme, IL-4 and TGF-β, but no interaction to the further reduction of the content of SIgA,J chain and pIgR mRNA expression. (3)Compared with the normoxic control group,the contents of lysozyme,IL-4 and TGF-I3 decreased significantly 2 weeks after the LHTL, and the TGF-β content decreased significantly 6 weeks after the LHTL. Compared with hypoxic training group,the contents of SIgA,RD-5, lysozyme ,LI-4 and TGF-β tended to increase 2 weeks after the LHTL without statistic difference ,while the J chain and plgR mRNA expression increased significantly. The contents of SIgA, RD-5, lysozyme', IL-4, TGF- β and pIgR mRNA expression increased signifi hypoxic exposure and intensive training could cantly 6 weeks after the LHTH. Conclusion (1)Both the inhibit the intestinal mucosa immune function,especially training under the hypoxic condition. (2)Intensive training could affect SIgA synthesis by inhibiting the formation