摘要
Abstract
Objective To investigate the effects of thyroid hormone( TH )on the nicotinic acetylcholine receptor α4( nAchRα/4 )expression in the developing period of rat hippocampus. Methods The Wistar rats were divided into normal group ( n = 42 ) and hypothyroidism group ( n = 36 ). The hypothyroidism model of rats was established by pre-treatment with thiamazole. The brain tissues of rats were collected at the postnatal day 0,4,7 ,14 .21 .30 and 120 in 2 groups. The expression of nAchRα4 mRNA in hippocampus was detected by in situ hybridization method. Results ①The nAchRα4 mRNA expression was significantly different at different postnatal days and distributed by layer. The nAchRα4 mRNA expression was very low at postnatal day 0 ( POd ), peaked at postnatal day 14 or 21 ,and then decreased to the level of adulthood rat( at postnatal day 120 ).②The peak expression of nAchRα4 mRNA was 4 - 5 times of the adulthood level in CAI of normal rats. about 8 times in CA2 , CA3 sectors , and about 5 times in dentate gyrus. ③Expression of nAchRα4 mRNA in hypothyroidism group was significantly lower than that in normal group( P ＜0. 001 ). The peak of nAchRa4 mRNA expression occurred at the same time in hypothyroidism group and normal group. Conclusion The results suggest that in the critical period of hrain growth, thyroid hormone decrease c:ould lead to the change of nAChRα4 mRNA expression in the rat hippocampus, and further affect the occurrence of synapses and establishment of related nerve circuit, the peerless of the neuronal place or mistaking of nerve thoroughfare , which may obstruct the brain development and function maturation.关键词
甲状腺激素/突触发育/海马/神经元烟碱受体α4亚单位Key words
thyroid hormone/ development of synapses/ hippocampus/ nicotinic acetylcholine receptor α4分类
医药卫生
