Fujikawa H, Kanno T, Nagata T, Nishizaki T. The phosphodiesterase III inhibitor olprinone inhibits hippocampal glutamate release via a cGMP/PKG pathway.
Neurosci Lett 2008;
448:208-11. [PMID:
18983890 DOI:
10.1016/j.neulet.2008.10.079]
[Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2008] [Revised: 10/16/2008] [Accepted: 10/21/2008] [Indexed: 11/19/2022]
Abstract
Olprinone, an inhibitor of cyclic nucleotide phosphodiesterase III, inhibited an increase in intracellular Ca(2+) concentrations for acutely dissociated rat hippocampal pyramidal neurons induced by extracellular high K(+) (35 mM) depolarization. Olprinone (100 microM) significantly reduced spontaneous glutamate release from rat hippocampal slices. Furthermore, olprinone significantly decreased the rate of alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptor-mediated miniature excitatory postsynaptic currents (AMPA-mEPSCs) monitored from CA1 pyramidal neurons of rat hippocampal slices, and the effect was blocked by KT5823, an inhibitor of protein kinase G (PKG), but not by H-89, an inhibitor of protein kinase A (PKA). In the PKA assay using PC-12 cells, olprinone did not activate PKA. Taken together, the results of the present study show that olprinone attenuates intracellular Ca(2+) rise through voltage-sensitive Ca(2+) channels and inhibits presynaptic glutamate release via a cGMP/PKG pathway.
Collapse