Characterization of the Effect of Monensin on ?-Amino-n-Butyric Acid Release from Isolated Nerve Terminals
- 1 August 1989
- journal article
- research article
- Published by Wiley in Journal of Neurochemistry
- Vol. 53 (2), 442-447
- https://doi.org/10.1111/j.1471-4159.1989.tb07354.x
Abstract
The action of the polyether antibiotic monensin on the release of .gamma.-[3H]amino-n-butyric acid ([3H]GABA) from mouse brain synaptosomes is characterized. Monensin enhances the release of this amino acid transmitter in a dose-dependent manner and does not modify the efflux of the nontransmitter amino acid .alpha.-[3H]aminoisobutyrate. The absense of external Ca2+ fails to prevent the stimulatory effect of monoensin on [3H]GABA release. Furthermore, monensin is less effective in stimulating [3H]GABA release in the presence of Ca2+. The releasing response to monensin is absolutely dependent on external Na+. The blockade of voltage-sensitive Na+ or Ca2+ channels does not modify monensin-induced release of the transmitter. Also, the blockade of the GABA uptake pathway fails to prevent the stimulatory effect of monensin on [3H]GABA release. Although monensin markedly increases Na+ permeability in synaptosomes, these data indicate that the Ca2+-independent monensin-stimulated uptake pathway. It is concluded that the entrance of Na+ through monensin molecules inserted in the presynaptic membrane might be sufficient to initiate the intraterminal molecular events underlying transmitter release.Keywords
This publication has 23 references indexed in Scilit:
- The effect of monensin on cell aggregation of normal and dystrophic human skin fibroblastsExperimental Cell Research, 1985
- Correlations Between Na+-K+ATPase Activity and Acetylcholine Release in Rat Cortical SynaptosomesJournal of Neurochemistry, 1981
- The action of the sodium ionophore, monensin, on transmitter release at the frog neuromuscular junctionBrain Research, 1980
- Immunocytochemical localization of procollagen and fibronectin in human fibroblasts: effects of the monovalent ionophore, monensin.The Journal of cell biology, 1980
- A reevaluation of veratridine as a tool for studying the depolarization-induced release of neurotransmitters from nerve endingsNeurochemical Research, 1980
- Mechanism of monensin-induced hyperpolarization of neuroblastoma-glioma hybrid NG108-15.Proceedings of the National Academy of Sciences, 1979
- K+-stimulated release of labeled γ-aminobutyrate, glycine and taurine in slices of several regions of rat central nervous systemNeuroscience, 1978
- Modulation of transmitter release by intracellular sodium in squid gland synapseBrain Research, 1977
- Uptake and Exchange of GABA and Glutamate in Isolated Nerve EndingsPublished by Springer Nature ,1976
- Tritosol: A new scintillation cocktail based on Triton X-100Analytical Biochemistry, 1975