一氧化氮在硒缺乏致鸡脾脏淋巴细胞凋亡中的作用

本文旨在研究一氧化氮(NO)在硒缺乏致鸡脾脏淋巴细胞凋亡中的作用.选择1日龄健康海蓝褐雏鸡80只,随机分为对照组和缺硒组2个组,每组4个重复,每个重复10只鸡,对照组鸡饲料中硒含量为0.282 mg/kg,缺硒组鸡饲料中硒含量为0.032 mg/kg.分别于30、45、60和75日龄每组随机抽取10只鸡采样,测定脾脏和血清谷胱甘肽过氧化物酶(GSH-Px)活性、NO含量、一氧化氮合酶(NOS)活性以及脾脏和全血中硒含量的变化;检测脾脏中诱导型一氧化氮合酶(iNOS)mRNA表达量变化和淋巴细胞的凋亡情况.结果表明,与对照组比较,缺硒组鸡脾脏和全血中硒含量降低;脾脏和血清中GSH-Px活性降低;NO含量、NOS活性及iNOS mRNA表达量升高;脾脏淋巴细胞DNA出现降解,呈现梯形条带,电镜下细胞核皱缩,核染色质边聚、固缩,线粒体肿胀,嵴溶解甚至消失,内质网排列紊乱、肿胀等呈现典型的细胞凋亡现象.本试验结果提示硒缺乏可引起鸡脾脏及血清NO代谢发生改变,导致脾脏淋巴细胞发生凋亡,表明NO在硒缺乏致鸡脾脏淋巴细胞凋亡中具有重要作用.

Effects of NO on Splenic Lymphocyte Apoptosis Induced by Selenium Deficiency in Chickens

The study was conducted the effects of NO on spleen lymphocyte apoptosis induced by selenium deficiency in chick-ens.Eighty one-day-old healthy chickens were randomly allocated into two groups (control group and selenium deficiency group) with four replicates and ten chickens in each replicate.Control group was fed a basal diet including 0.282 mg/kg Se, and selenium deficiency group was given a basal diet including 0.032 mg/kg Se.The samples were obtained from ten chickens at 30, 45, 60, 75 days of age in each group, and the activities of GSH-Px and NOS, the content of NO in spleen and serum, the content of selenium in spleen and whole blood, and the expression of iNOS mRNA and the lymphocyte apoptosis in spleen were detected.The results showed that, compared with control group, the content of selenium in spleen and whole blood and activity of GSH-Px in spleen and serum of the chickens in selenium deficiency group decreased while the content of NO, the activity of NOS and the expression of iNOS in spleen and serum increased, and the DNA of splenic lymphocyte was degraded and a ladder band appeared.Typical apoptosis was found in splenic lymphocyte of the chickens in selenium defi-ciency group by electron microscope, including cell shrinkage, nuclear chromatin margination and condensation, mitochon-drial swelling and dissolution or disappearance of cristae, disorder and swelling of endoplasmic reticulum.It was concluded that selenium deficiency could induce the change of NO metabolism, and lead to apoptosis of splenic lymphocyte of chickens, and it further demonstrated NO played an important role in splenic lymphocyte apoptosis of chickens.