-transparent.png){kind=logo}
Calcium antagonists inhibit both the Ca2(+)-dependent and -independent release of endogenous glutamate from intact synaptosomes. In the present study, the inhibitory potency of several different classes of calcium antagonists were determined under conditions that control for an effect of these compounds on the Ca2(+)-independent component of glutamate release. The following order of inhibitory potency was derived: flunarizine and cinnarizine greater than diltiazem greater than verapamil, nifedipine and nimodipine greater than omega-conotoxin much greater than amiloride, phenytoin, gadolinium and nickel. Only the diphenylpiperazine derivatives inhibited Ca2(+)-dependent glutamate release with an IC50 value of less than 10(-5) M. This finding indicates that no one type of presynaptic calcium channel predominantly mediates Ca2(+)-dependent glutamate release from hippocampal mossy fiber terminals. It is suggested that the exocytosis of glutamate from rat hippocampal mossy fiber synaptosomes may be mediated by multiple types of calcium channels.
D M Terrian, and
R V Dorman, and
R L Gannon
December 1989,
Neuroscience letters,
D M Terrian, and
R V Dorman, and
R L Gannon
September 1988,
Brain research bulletin,
D M Terrian, and
R V Dorman, and
R L Gannon
March 1992,
Neuroscience letters,
D M Terrian, and
R V Dorman, and
R L Gannon
January 2002,
Science (New York, N.Y.),
D M Terrian, and
R V Dorman, and
R L Gannon
February 2024,
Biomedicines,
D M Terrian, and
R V Dorman, and
R L Gannon
June 1991,
Brain research,
D M Terrian, and
R V Dorman, and
R L Gannon
February 2005,
Neuron,
D M Terrian, and
R V Dorman, and
R L Gannon
February 2002,
Journal of neurophysiology,
D M Terrian, and
R V Dorman, and
R L Gannon
August 1993,
Journal of neurochemistry,
D M Terrian, and
R V Dorman, and
R L Gannon
September 2001,
Proceedings of the National Academy of Sciences of the United States of America,
