Cyclothiazide Selectively Potentiates AMPA- and Kainate-Induced [3H]Norepinephrine Release from Rat Hippocampal Slices
Version of Record online: 23 NOV 2002
Journal of Neurochemistry
Volume 63, Issue 1, pages 231–237, July 1994
How to Cite
Desai, M. A., Burnett, J. P. and Schoepp, D. D. (1994), Cyclothiazide Selectively Potentiates AMPA- and Kainate-Induced [3H]Norepinephrine Release from Rat Hippocampal Slices. Journal of Neurochemistry, 63: 231–237. doi: 10.1046/j.1471-4159.1994.63010231.x
- Issue online: 23 NOV 2002
- Version of Record online: 23 NOV 2002
- Received October 5, 1993; revised manuscript received November 22, 1993; accepted December 6, 1993.
- AMPA receptor;
- [3H]Norepinephrine release;
- Receptor desensitization
Abstract: Activation of the α-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) subtype of ionotropic glutamate receptors has been shown to result in a rapid desensitization of the receptor in the presence of certain agonists. One effect of AMPA receptor desensitization in the hippocampus may be to decrease the efficacy of AMPA receptor agonists at stimulating the release of norepinephrine from noradrenergic terminals. Recently, cyclothiazide was reported to inhibit AMPA receptor desensitization by acting at a distinct site on AMPA receptors. We have examined the effect of cyclothiazide on AMPA- and kainate (KA)-induced norepinephrine release from rat hippocampal slices to determine whether cyclothiazide would increase the efficacy of AMPA-induced [3H]norepinephrine release by inhibiting AMPA receptor desensitization. Cyclothiazide was observed to potentiate markedly both AMPA- and KA-induced [3H]norepinephrine release. This potentiation is selective for AMPA/KA receptors as cyclothiazide did not potentiate N-methyl-d-aspartate-induced [3H]norepinephrine release or release induced by the nonspecific depolarizing agents veratridine and 4-aminopyridine. These results demonstrate that AMPA receptor-mediated modulation of [3H]norepinephrine release from rat brain slices is a useful approach to studying the cyclothiazide modulatory site on the AMPA receptor complex.