Effects of Long Term Injection of Sodium Salicylate on the ABR and Expression of GAD67 in Rat Inferior Colliculus / 听力学及言语疾病杂志

ABSTRACT

Objective To observe the effects of long term injection sodium salicylate on the auditory brain-stem response(ABR)and expression of glutamic acid decarboxylase -67(GAD67) in rat inferior colliculus .Methods Eighteen healthy Wistar rats were randomly divided into three groupsthe sodium salicylate group (intramuscular injection of 10% sodium salicylate ,175 mg/kg ,twice daliy for 28 days) ,the saline group (intramuscular injection with saline on same does at the same time) ,the control group (without any treatment) .The rats received ABR after modeling ,then were decapitated and inferior colliculus tissues were stripped .Western blot was used to study the dif-ferent expression of GAD67 protein levels in the three groups .Results Compared with the saline group and control group ,ABR thresholds of the sodium salicylate group were significantly elevated and latency of wave Ⅲ was aslo sig-nificantly prolonged(P0 .05) .The inferior colliculus GAD67 protein expression level of sodium salicylate group was significantly higher than the saline group and control group(P0 .05) .Conclusion Long term injection of sodium salicylate can cause a change in the inferior colliculus of GAD67 protein expression and the up regulation of GAD67 expression may occur as a com-pensatory response to increase inhibiting effect .The change of GAD67 protein expression is likely as a compensatory and regulatory mechanisms for sodium salicylate ototoxicity .