Ionic Regulation of the Binding of dl-[3H]2-Amino-4-Phosphonobutyrate to l-Glutamate-Sensitive Sites on Rat Brain Membranes
- 1 October 1984
- journal article
- research article
- Published by Wiley in Journal of Neurochemistry
- Vol. 43 (4), 1039-1045
- https://doi.org/10.1111/j.1471-4159.1984.tb12841.x
Abstract
The effects of ions on the binding of the excitatory amino acid analog DL-[3H]2-amino-4-phosphonobutyrate to L-glutamate-sensitive sites on rat brain synaptic membranes was investigated. The divalent cations Mg, Mg, Sr, and particularly Ca, produced a marked enhancement in specific binding. This effect was manifest only in the presence of added chloride, or to a lesser extent, with bromide ions. Application of saturation analysis revealed that both chloride and Ca acted to increase the binding site density in a concentration-dependent manner, without affecting the dissociation constant. The only other ionic species found to have a significant effect on 2-amino-4-phosphonobutyrate binding was Na, which produced an apparent reduction in site affinity, without modifying the binding site density. Although the significance of these striking ionic effects is as yet unknown, it seems feasible that chloride (and possibly also Ca) ions may serve a role in regulating the interaction of excitatory amino acids with their physiological receptors.Keywords
This publication has 15 references indexed in Scilit:
- Characterization of the binding of dl‐[3H]‐2‐amino‐4‐phosphonobutyrate to l‐glutamate‐sensitive sites on rat brain synaptic membranesBritish Journal of Pharmacology, 1983
- Chloride and calcium ions separte L-glutamate receptor populations in synaptic membranesEuropean Journal of Pharmacology, 1983
- Some effects of excitatory amino acid receptor antagonists on synaptic transmission in the rat olfactory cortex sliceBrain Research, 1982
- Chloride ions enhance L-glutamate binding to rat brain synaptic membranesBrain Research, 1982
- Chloride and calcium ions reveal a pharmacologically distinct population of L-glutamate binding sites in synaptic membranes: correspondence between biochemical and electrophysiological dataJournal of Neuroscience, 1982
- Micromolar Calcium Stimulates Proteolysis and Glutamate Binding in Rat Brain Synaptic MembranesScience, 1981
- Distinct pharmacological properties of excitatory amino acid receptors in the rat striatum: study by Na+ efflux assay.Proceedings of the National Academy of Sciences, 1981
- Pharmacology of excitatory amino acid receptors mediating the stimulation of rat cerebellar cyclic GMP leveleLife Sciences, 1980
- Regulation of glutamate receptors by cationsNature, 1979
- HIGH AFFINITY l‐[3H]GLUTAMATE BINDING TO POSTSYNAPTIC RECEPTOR SITES ON RAT CEREBELLAR MEMBRANESJournal of Neurochemistry, 1978