N-乙酰半胱氨酸预防大鼠模拟空气反复潜水后的免疫抑制

目的 :观察 N-乙酰半胱氨酸 (NAC)对大鼠模拟空气反复潜水后免疫抑制的预防作用。方法 :以添加 NAC的饲料喂养大鼠 6 d,第 4天开始以 70 0 k Pa压缩空气反复暴露 3d,每天 2次每次 6 0 m in(8:0 0～ 9:0 0 ,14 :0 0～ 15 :0 0 )。于暴露后次日晨断头取血及脾脏。用流式细胞术测定外周血及脾淋巴细胞亚型 ,用 3H- Td R掺入法测定脾淋巴细胞增殖反应 ,以 EL ISA法测定循环血浆及脾淋巴细胞经刀豆球蛋白 (Con A)刺激后分泌的 IL - 2水平以及比色法测定血浆中超氧化物歧化酶 (SOD)、过氧化氢酶 (CAT)、谷胱甘肽过氧化物酶 (GPx)、谷胱甘肽 S转移酶 (GST)的活力和还原型谷胱甘肽 (GSH )、丙二醛 (MDA )的含量。结果 :添加 NAC的食物对外周血及脾淋巴细胞亚型变化无显著影响 ;食物中添加 0 .2 %的 NAC后 ,血浆及脾淋巴细胞经 Con A刺激后分泌的 IL - 2水平及脾淋巴细胞增殖率比正常食物组有明显提高 (P<0 .0 5 ,P<0 .0 1) ,血浆抗氧化酶活力及GSH浓度明显高于对照组 (P<0 .0 5 ) ,而 MDA则显著减少 (P<0 .0 5 )。 结论 :食物中 NAC对高压空气反复暴露引起大鼠的免疫抑制有一定预防作用

Preventive effect of N-acetylcysteine on immunosuppression after simulated air repetitive diving in rats

Objective:To examine the protective effect of N acetylcysteine (NAC) on the immunosuppression after repetitive simulated air diving in rats.Methods:Adult rats were fed with NAC additive food for 6 d.On the 4th day all rats were placed in an animal chamber(700 kPa air,for 60 min) twice a day (8:00 9:00,14:00 15:00) for 3 d.Peripheral blood and spleen were sampled after decapitation on the morning following exposures.The subpopulations of lymphocytes in blood and spleen were identified using 3 coloured flow cytometry. 3H TdR incorporation were used to assess the proliferation rate of splenic lymphocytes.IL 2 in plasma or excreted by splenic lymphocytes after ConA stimulation were determined with ELISA.Activities of superoxide dismutase (SOD),catalase (CAT),glutathione peroxidase (GPx),glutathione S transferase (GST) and levels of glutathione (GSH),methylenedioxyamphetamine (MDA) in plasma were determined by colorimetry.Results:Food added with NAC didnot affect the lymphocytes subpopulations changes caused by repetitive hyperbaria exposures.NAC(0.2%) in food prevented the decreases of splenic lymphocyte proliferation rate( P <0.01) and the IL 2 in plasma or excreted by splenic lymphocyte after ConA stimulation ( P <0.05).And the plasma activities of anti oxidases and GSH level were greater than that of the normal food group ( P <0.05), while MDA level was lower ( P <0.05) than the control.Conclusion:NAC in food has preventive effect against repetitive hyperbaric air exposures on immune functions in rats to some extent.