长期递增负荷运动对大鼠肠系膜淋巴结结构及淋巴细胞凋亡的影响  

Effects of Long-term Incremental Exercise on Structure and Lymphocyte Apoptosis of Mesenteric Lymph Nodes in Rats

作　　者：丁响[1] 覃飞[2] 周小青[3] 

机构地区：[1]上海海事大学体育部,上海201306 [2]华南师范大学体育科学学院,在读博士生广州510006 [3]北京体育大学武术学院,北京110084

出　　处：《体育与科学》2016年第2期115-120,共6页Sports & Science

摘　　要：目的:观察6周递增负荷运动过程中,大鼠肠系膜淋巴结形态结构及淋巴细胞凋亡的基本特征,探讨过度运动对肠道粘膜免疫功能的影响及其相关机制。方法:雄性SD大鼠64只,随机分为安静对照组(32只)和运动组(32只),运动组进行六周递增负荷跑台运动,分别在第1天及第2、4、6周末观察肠系膜淋巴结的形态学变化,并通过淋巴细胞Bax、Bcl-2表达和SOD、MDA水平探讨对淋巴细胞凋亡的影响。结果:1)肠系膜淋巴结的结构发生进行性破坏,主要表现为皮质、副皮质淋巴小结及生发中心数目减少,皮质和髓质交叉融合、面积比下降、细胞密度降低;2)Bax/Bcl-2比值升高,提示淋巴细胞凋亡增多且主要出现在肠系膜淋巴小结的生发中心;3)肠系膜淋巴结内脂质过氧化物(MDA)持续性增多。研究结果提示,大强度运动导致的自由基生成增多,可诱发Bcl-2蛋白下调,进一步导致淋巴细胞凋亡增多。结论:肠系膜淋巴结结构改变,淋巴细胞过度凋亡可能是长期大负荷运动诱发肠道粘膜免疫机能抑制的主要原因之一。Objective：To survey the changes in histological structure and lymphocyte apoptosis of mesenteric lymph nodes in rats during long-term incremental exercise.Methods：64Sprague-Dawle rats,aged 8 weeks,were divided into Control and Exercise Group,the latter performed 6-week incremental treadmill exercise.Samples were taken first day（Week0）,in the end of Week 2,Week 4and Week 6respectively.Then following parameters were measured：HE staining,expression of Bax and Bcl-2of lymphocyte,and concentration of MDA and SOD.Results：1）The progressive destruction of mesenteric lymph nodes structure as follows：decreased the number of follicular and germinal centers in cortex and paracortex;decrease in the ratio of cortical area to medullary area;loss of cellularity in the cortex and medulla;blurred of dividing line in the cortex and medulla.2）The up-regulated Bax/Bcl-2in week2 and week6implied increased lymphocyte apoptosis occurred in germinal center of follicle.3）MDA gradually increased may be one of the reason of Bcl-2sharply down-regulated.Conclusion：These results implied that increased free radicals,induced by exercise,may be one of the mechanisms of gut lymphocyte apoptosis.

关 键 词：运动免疫 肠系膜淋巴结 淋巴细胞凋亡 自由基 

分 类 号：G804.2[文化科学—运动人体科学]