大鼠脑干下丘中央核5-羟色胺表达与年龄相关性变化

摘要

目的:观察分析5-羟色胺(5-Hydroxytryptamine,5-HT)在青年鼠(3月龄)、成年鼠(12月龄)和老年鼠(24月龄)脑干下丘中的表达,比较其表达的差异性,探讨该差异的原因及可能的生理作用.方法:采用免疫组织化学ABC法检测青年鼠、成年鼠、老年鼠脑干下丘中央核组织中5-HT的表达.结果:青年鼠、成年鼠与老年鼠脑干下丘核团中,5-HT能神经元与神经纤维分布广泛,多个区域均可见5-HT阳性神经元,主要分布于脑干下丘中央部核团中.老年鼠脑干下丘中央核5-HT能神经元的数量及免疫反应性均低于青年和成年鼠(P0.05).老年鼠5-HT灰度值均较青年鼠和成年鼠显著增大(P<0.01).结论:老年鼠脑干下丘中央核5-HT表达呈现明显的老年衰退现象,此现象可能与5-HT的合成、重摄取及代谢分解功能的变化有关,对脑干下丘水平听觉信息的调制可能有重要影响.%Objective: To observe the expression of 5-Hydroxytryptamine (5-HT) and the distinction of its distribution in the inferior culliculus in young,adult and old rats(3,12 and 24 months old) and to explore the possibly physiological cause as well as the effect. Methods:The expressions of 5-HT among young rats,adult rats and old rats were examined by immunohistochemistry. Results:5-HT immunoreactive cells and fibers were widely distributed in some regions of inferior culliculus 5-HT immunoreactive cells appeared mainly in inferior culliculus central (ICC) , while the stronger labelled fibers mainly in ICC ventral. The old rats exhibited less in the number and weaker in immunoreaction than that in young adult rats ( P < 0. 01 ). Conclusions: The expression of 5-HT showed significantly age-related changes, which were related to the functional changes of synthesis, re-incept as well as metabolizability, and probably affect the modulation to the information of auditory input in the inferior culliculus during aging.