Salicylate blocks L-type calcium channels in rat inferior colliculus neurons.
To investigate the effects of the tinnitus inducer sodium salicylate on L-type voltage-gated calcium channels, we studied freshly dissociated inferior colliculus neurons of rats by the whole-cell voltage clamp method. Salicylate's blocking of L-type calcium channels was concentration dependent, and the IC(50) value of salicylate was estimated to be 1.99 mM. An amount of 1 mM salicylate significantly shifted the steady-state inactivation curve of L-type calcium channels about 9 mV in the hyperpolarizing direction and significantly delayed calcium channel recovery. Our results suggest that salicylate's blocking of L-type calcium channels may contribute to salicylate-induced tinnitus by decreasing GABA release in the inferior colliculus.
Liu
Yanxing
Y
Department of Neurobiology, Hebei Medical University, No. 361 Zhongshan East Road, Changan District, Shijiazhuang 050017, PR China. liuyanxing75@sohu.com
Li
Xuepei
X
Ma
Changsheng
C
Liu
Junxiu
J
Lu
Hong
H
D000818:Animals; D002121:Calcium Channel Blockers / Q000494:pharmacology*; D020746:Calcium Channels, L-Type / Q000032:analysis / Q000187:drug effects*; D005260:Female; D007245:Inferior Colliculi / Q000166:cytology / Q000503:physiopathology*; D015640:Ion Channel Gating / Q000187:drug effects / Q000502:physiology; D008297:Male; D009474:Neurons / Q000187:drug effects* / Q000378:metabolism; D018408:Patch-Clamp Techniques; D051381:Rats; D017208:Rats, Wistar; D012980:Sodium Salicylate / Q000009:adverse effects / Q000494:pharmacology*; D014012:Tinnitus / Q000139:chemically induced / Q000503:physiopathology
D002121:Calcium Channel Blockers; D020746:Calcium Channels, L-Type; D012980:Sodium Salicylate