NOS在甲状腺功能低下小鼠脑中含量变化的研究

本文研究了甲状腺激素减少时,小鼠的大脑、小脑、海马、嗅脑等脑组织中一氧化氮合酶（NOS）含量的变化.采用丙硫氧嘧啶（PTU）持续灌注20日龄左右雌性昆明小鼠造成甲减模型.采用NOS的生化测定法检测甲减小鼠的大脑、小脑、嗅脑、海马等中的NOS含量;检测指标包括组织中总一氧化氮合酶（TNOS）活性,以及诱导型一氧化氮合酶（iNOS）及结构型一氧化氮合酶（cNOS）两种分型酶的活性.生化测定法显示,甲状腺功能低下小鼠NOS含量与对照组比较在大脑、小脑和嗅脑中均出现了下降,cNOS在大脑、小脑、海马、嗅脑部位也均出现了下调.而iNOS含量在甲状腺功能低下小鼠的大脑、小脑、海马、嗅脑中却出现了上调.由此可得出,甲状腺激素的分泌异常会造成NOS含量的异常,NO信号系统可能参与甲状腺激素缺乏所致的脑损害过程.

Study on the Nitric Oxide Synthase Activity Changes in the Hypothyroid Mice Brain

Object：In this study,we investigated the effects of thyoid hormone status on the nitric oxide synthase（NOS） content changes in the hypothyroid mice.Methods： Hypothyroid mice were induced by intragastric administration of propylthiouracil（PTU） for 4 weeks.The NOS activity in the hypothyroid brain,including cerebral cortex,cerebellum,olfactory bulb and hippocampus,was examined.The activities of different subtypes of the total NOS,induced NOS（iNOS） and constitutive NOS（cNOS） were also analyzed.Results： The NOS activity decreased in the cerebral cortex,cerebellum and olfactory of hypothyroid mice.The cNOS content in the cerebral cortex,cerebellum,olfactory bulb and hippocampus was also down-regulated while the iNOS activity in the hypothyroid mice brain increased compared with control group.Conclusion： These results indicated that the abnormal of thyroid hormone secretion would affect NOS activity in the brain.And the NO signaling system may be involved in the process of brain damage induced by thyroid hormone deficiency.