GluR2 expression in developing rat cochlear nucleus and relationship with development of synapse / 上海第二医科大学学报

ABSTRACT

Objective To investigate the trend of developmental expression of GluR2,subtype of alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid(AMPA) receptor and synaptophysin(SYP) in the rat cochlear nucleus(CN) in different developmental stages,and explore the association of GluR2 expression with the development of synapse. Methods SD rats of 2,3,4,6,8 and 10 weeks old were selected,the expression of GluR2 and SYP in CN was detected with immunofluorescence histochemical method,and the association of them was explored. Results GluR2 expression was observed in all the neurons of CN in each postnatal groups.The expression was relatively weaker in the second and third week,became denser in the fourth week,reached the peak in the sixth week and then sharply decreased to the weakest in the tenth week.The expression of GluR2 was denser at granular cell layer,while weaker at molecular layer and multipolar cell layer in the dorsal CN.SYP expression was detected in all the neurons of CN in each postnatal groups.The expression was weakest in the second week,significantly denser in the fourth week,reached the peak in the sixth week,was then sharply decreased and stably maintained. Conclusion The expressions of GluR2 and SYP in the postnatal rat CN exhit an equally age-dependent tendency.The expression of GluR2 in the CN may be associated with the the maturation and function development of the CN.The different expression and distribution of GluR2 and SYP in the rat CN of different developmental stages may be involved in the development and plasticity of auditory center.