不同运动负荷对大鼠cNOS和iNOS活性的影响及其机理探讨

方法：４０只ＳＤ大鼠，随机分为对照组、４５ｍｉｎ训练组、９０ｍｉｎ训练组、１５０ｍｉｎ训练组和急性力竭组，进行无负重游泳训练８周，每周６次。测定大鼠胸主动脉构建型一氧化氮合酶（ｃＮＯＳ）、诱导型一氧化氮合酶（ｉＮＯＳ）及腹腔巨噬细胞ｉＮＯＳ的活性和血液中ＮＯ、ＣＤ４＋／ＣＤ８＋的变化。结果：９０ｍｉｎ训练组、１５０ｍｉｎ训练组胸主动脉ｃＮＯＳ活性显著上升，与之相对应的血浆ＮＯ的水平也显著上升（Ｐ＜０．０５）。急性力竭组胸主动脉ｉＮＯＳ水平显著上升（Ｐ＜０．０５）。１５０ｍｉｎ训练组及力竭运动组腹腔巨噬细胞ｉＮＯＳ与对照组相比显著上升（Ｐ＜０．０５）。血液ＣＤ４＋／ＣＤ８＋的比值在９０ｍｉｎ训练组、１５０ｍｉｎ训练组均显著上升（Ｐ＜０．０５），而在急性力竭组则显著下降。结论：（１）适量的运动训练可引起胸主动脉ｃＮＯＳ活性增强，可能是适量运动改善心血管功能的机制之一。（２）适量的运动训练可以引起腹腔巨噬细胞ｉＮＯＳ活性适度增加，增强机体的非特异性免疫力。而力竭运动引起的腹腔巨噬细胞ｉＮＯＳ的活性的过度增强，则可能与大强度运动引起的细胞免疫抑制有关。

Influence and its Mechanism of Different Workload Exercise on the Activity of cNOS, iNOS in Rats

Objective To study the adjustment mechanism of different workload exercise s influence on cardiovascular and immune system. Results Compared with the control group, The thoracic aorta cNOS activity, plasma NO level and CD4+/CD8+ in 90 mm and 150 mm training groups increased significantly (P < 0.05), iNOS activity in acute exhausting group increased (P < 0.05), iNOS activity in peritoneal macrophage in 150 mm training group and acute exhausting group increased (P < 0.05), CD4+/CD8+ in acute exhausting group was lower than that in control group. Conclusion (I )Thoratic aorta cNOS activity increasing indicates that moderate exercise training may improve the cardiovascular function. (2)Moderate exercise training can induce moderate increase of iNOS activity in peritoneal macrophage, which may enhance the non-peculiar immunity. The excessive increase of iNOS activity in exhausting group may relate to the depression of cellular immunity induced by heavy load training.