The Effect Of Sodium Salicylate On The Internalization Of NMDA Receptor In Spiral Ganglion Neurons

Objective To study of the effects of sodium salicylate on the expression and internalization of NMDA receptor in spiral ganglion neurons(SGN),and further to explore the underlying mechanism about ototoxicity.Methods Immunocytochemistry was employed to detect NR1 subunit of NMDA receptor in primary cultured cells.The total and surface protein of NR1 subunit of NMDA receptor in the cell(Omin to 6h)were detected by cell surface biotinylation and western blot.Results Expression of NR1 subunit of NMDA receptor were detected in SGN.Compared with control group,sodium salicylate(5mM)had no effect on the total protein level of NR1 in 5min,15min and 30min(p>0.05).However,the surface protein level of NR1 was decreased effectively,which suggest internalization of NR significantly was increased(P<0.05).If a prolonged application of sodium salicylate was given to the cell(1h-6h),the total protein level significantly increased(P<0.05),With the increasing time of sodium salicylate,the total protein level increased.But internalization was stabilization.Whereas dynamin inhibitory peptide(DIP)could inhibit the internalization of NMDA receptor which caused by Sodium salicylate.Conclusion Expression of NMD A receptor in SGN;Sodium salicylate can enhances NMDA receptor internalization in the short time,increased NMDA receptor expression in the long time,and regulated NMDA receptor internalization by dynamin or Clathrin.