目的:研究胆囊收缩素(CCK)在小鼠海马发育过程中的表达,探索其生理功能。方法:免疫荧光法对海马锥体细胞、颗粒细胞中的胆囊收缩素阳性细胞以及齿状回分子层基质中胆囊收缩素阳性反应带进行标记,并统计胆囊收缩素阳性细胞在成熟神经细胞中的比例。结果:胆囊收缩素于生后第7天(P7)在海马锥体细胞和颗粒细胞中表达,随年龄增加,胆囊收缩素表达增多、增强,到成年约有60.1%的锥体细胞和颗粒细胞表达胆囊收缩素。胆囊收缩素还可以在胞外基质表达,主要是在齿状回内1/3分子层。结论:胆囊收缩素作为神经递质与调质广泛分布于海马成熟的锥体细胞和颗粒细胞,其意义可能与海马成熟、学习、记忆等功能相关。胆囊收缩素也可以分泌到齿状回内分子层基质中,可能是作为排斥分子信号参与穿通纤维寻径。
Objective: To investigate the cholecystokinin (CCK) expression in the mouse developing hippocampus and discuss its physiological functions. Methods: With immunofluorescent assays, the CCK positive cells in the pyramidal cells and granule cells in hippocampus and CCK positive reaction zone in the matrix of dentate gyrus were labeled. In the meantime, the proportion of CCK positive cells among the mature neurons was measured. Results: CCK initially expressed in the py ramidal cells and granule cells at postnatal day 7 (PT). With age increasing, CCK expression increased, and in adult 60. 1 pyramidal cells and granule cells expressed CCK. CCK was expressed in extracellular matrix, mainly in the inner molecular layer of dentate gyrus. Conelusion: As neurotransmitter and neuromodulator, CCK can distribute in the pyramidal cells and granule cells of hippoeampus widely. Its functions are probably involved in hippocampal development, learning and study. CCK can be secreted into the matrix of inner molecular layer of dentate gyrus, as a repulsive molecular signal for perforant path finding.