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Journal articles
Trimetazidine modulates AMPA/kainate receptors in rat vestibular ganglion neurons.
Abstract : Trimetazidine (1[2,3,4-trimethoxy-benzyl] piperazine, 2 HCl) is an anti-ischemic agent frequently administered as a prophylactic treatment for episodes of angina pectoris and chorioretinal disturbances. It is also employed as a symptomatic treatment of vertigo but its mechanism of action is yet to be defined. Using Fura-2 fluorescence photometry and whole-cell patch-clamp recordings we investigated the effect of trimetazidine on the [Ca(2+)](i) and current responses induced by the application of non-N-methyl-D-aspartate (NMDA) receptor agonists on low density vestibular ganglion neuronal cultures explanted from 3 day s postnatal rats. Trimetazidine blocked the [Ca(2+)](i) and current responses induced by 100 microM applications of both kainate and alpha-amino-3-hydroxy-5-methyl-4-isoxazolepropionate (AMPA). These responses were dependent on external Ca(2+) and were blocked by the voltage-dependent Ca(2+) channel blockers Ni(2+) and Cd(2+) . Trimetazidine only acts on the AMPA/kainate receptors and had no effect on K(+)-induced depolarizations. Dose-dependent curves were obtained for the inhibition by 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) and trimetazidine (IC(50) 7 microM and 0.7 microM) of kainate stimulations. After AMPA stimulation, dose-response inhibition curves showed an IC(50) of 3 microM for CNQX and 25 microM for trimetazidine. These results indicate that trimetazidine could be a potent antagonist of AMPA/kainate receptors in vestibular ganglion neurons. This may explain the protective role of trimetazidine in the inner ear suggesting an anti-excitotoxic activity.
Cited literature [37 references]
https://www.hal.inserm.fr/inserm-00173632
Contributor : Christian Hamel <>
Submitted on : Thursday, September 20, 2007 - 12:05:21 PM
Last modification on : Thursday, March 5, 2020 - 6:38:43 PM
Long-term archiving on: : Friday, November 25, 2016 - 5:49:37 PM
Contributor : Christian Hamel <>
Submitted on : Thursday, September 20, 2007 - 12:05:21 PM
Last modification on : Thursday, March 5, 2020 - 6:38:43 PM
Long-term archiving on: : Friday, November 25, 2016 - 5:49:37 PM