Ionic regulation of glutamate binding sites

E. E. Mena, S. R. Whittemore, D. T. Monaghan, C. W. Cotman

Research output: Contribution to journalArticle

16 Citations (Scopus)

Abstract

Cl- and Ca2+ increase glutamate binding to rat synaptic plasma membranes (SPMs) by revealing a distinct class of L-glutamate (L-Glu) binding sites. The present study was conducted to examine both the anion specificity of this response and the nature of the interaction between Cl- and Ca2+. Of the anions tested, Br- was the most effective in increasing the levels of L-Glu binding. Other effective anions were Cl-, NO3- and formate while F-, HCO3-CIO4-, propionate, SO42- and PO43- were ineffective. The anion specificity was similar to that observed for the Cl- membrane channel, suggesting that this binding site and the ion channel may be related. In the absence of Cl-, Ca2+ has little effect on L-Glu binding. Increasing the Cl- concentration increased the apparent affinity (decreased KCa2+) of the Ca2+-stimulated, L-Glu binding component and also decreased the maximal amount of the enhancement. Conversely, increasing Ca2+ levels increased the maximal enhancement of L-Glu binding brought about by Cl- without affecting the KCl- of the effect. Prior incubation of membranes with Ca2+ did not raise the level of L- Glu binding. Furthermore, EGTA was able to reverse the stimulation of L- Glu binding due to Ca2+. The results indicate that Ca2+ acts ionically to enhance L-Glu binding to rat SPMs.

Original languageEnglish (US)
Pages (from-to)2427-2433
Number of pages7
JournalLife Sciences
Volume35
Issue number24
DOIs
StatePublished - Dec 10 1984

Fingerprint

Glutamic Acid
Binding Sites
Anions
Synaptic Membranes
formic acid
Cell membranes
Ion Channels
Rats
Cell Membrane
Egtazic Acid
Propionates
Membranes

ASJC Scopus subject areas

  • Biochemistry, Genetics and Molecular Biology(all)
  • Pharmacology, Toxicology and Pharmaceutics(all)

Cite this

Mena, E. E., Whittemore, S. R., Monaghan, D. T., & Cotman, C. W. (1984). Ionic regulation of glutamate binding sites. Life Sciences, 35(24), 2427-2433. https://doi.org/10.1016/0024-3205(84)90451-X

Ionic regulation of glutamate binding sites. / Mena, E. E.; Whittemore, S. R.; Monaghan, D. T.; Cotman, C. W.

In: Life Sciences, Vol. 35, No. 24, 10.12.1984, p. 2427-2433.

Research output: Contribution to journalArticle

Mena, EE, Whittemore, SR, Monaghan, DT & Cotman, CW 1984, 'Ionic regulation of glutamate binding sites', Life Sciences, vol. 35, no. 24, pp. 2427-2433. https://doi.org/10.1016/0024-3205(84)90451-X
Mena, E. E. ; Whittemore, S. R. ; Monaghan, D. T. ; Cotman, C. W. / Ionic regulation of glutamate binding sites. In: Life Sciences. 1984 ; Vol. 35, No. 24. pp. 2427-2433.
@article{199a5d264cf54b648bfcc37e0e4eb43b,
title = "Ionic regulation of glutamate binding sites",
abstract = "Cl- and Ca2+ increase glutamate binding to rat synaptic plasma membranes (SPMs) by revealing a distinct class of L-glutamate (L-Glu) binding sites. The present study was conducted to examine both the anion specificity of this response and the nature of the interaction between Cl- and Ca2+. Of the anions tested, Br- was the most effective in increasing the levels of L-Glu binding. Other effective anions were Cl-, NO3- and formate while F-, HCO3-CIO4-, propionate, SO42- and PO43- were ineffective. The anion specificity was similar to that observed for the Cl- membrane channel, suggesting that this binding site and the ion channel may be related. In the absence of Cl-, Ca2+ has little effect on L-Glu binding. Increasing the Cl- concentration increased the apparent affinity (decreased KCa2+) of the Ca2+-stimulated, L-Glu binding component and also decreased the maximal amount of the enhancement. Conversely, increasing Ca2+ levels increased the maximal enhancement of L-Glu binding brought about by Cl- without affecting the KCl- of the effect. Prior incubation of membranes with Ca2+ did not raise the level of L- Glu binding. Furthermore, EGTA was able to reverse the stimulation of L- Glu binding due to Ca2+. The results indicate that Ca2+ acts ionically to enhance L-Glu binding to rat SPMs.",
author = "Mena, {E. E.} and Whittemore, {S. R.} and Monaghan, {D. T.} and Cotman, {C. W.}",
year = "1984",
month = "12",
day = "10",
doi = "10.1016/0024-3205(84)90451-X",
language = "English (US)",
volume = "35",
pages = "2427--2433",
journal = "Life Sciences",
issn = "0024-3205",
publisher = "Elsevier Inc.",
number = "24",

}

TY - JOUR

T1 - Ionic regulation of glutamate binding sites

AU - Mena, E. E.

AU - Whittemore, S. R.

AU - Monaghan, D. T.

AU - Cotman, C. W.

PY - 1984/12/10

Y1 - 1984/12/10

N2 - Cl- and Ca2+ increase glutamate binding to rat synaptic plasma membranes (SPMs) by revealing a distinct class of L-glutamate (L-Glu) binding sites. The present study was conducted to examine both the anion specificity of this response and the nature of the interaction between Cl- and Ca2+. Of the anions tested, Br- was the most effective in increasing the levels of L-Glu binding. Other effective anions were Cl-, NO3- and formate while F-, HCO3-CIO4-, propionate, SO42- and PO43- were ineffective. The anion specificity was similar to that observed for the Cl- membrane channel, suggesting that this binding site and the ion channel may be related. In the absence of Cl-, Ca2+ has little effect on L-Glu binding. Increasing the Cl- concentration increased the apparent affinity (decreased KCa2+) of the Ca2+-stimulated, L-Glu binding component and also decreased the maximal amount of the enhancement. Conversely, increasing Ca2+ levels increased the maximal enhancement of L-Glu binding brought about by Cl- without affecting the KCl- of the effect. Prior incubation of membranes with Ca2+ did not raise the level of L- Glu binding. Furthermore, EGTA was able to reverse the stimulation of L- Glu binding due to Ca2+. The results indicate that Ca2+ acts ionically to enhance L-Glu binding to rat SPMs.

AB - Cl- and Ca2+ increase glutamate binding to rat synaptic plasma membranes (SPMs) by revealing a distinct class of L-glutamate (L-Glu) binding sites. The present study was conducted to examine both the anion specificity of this response and the nature of the interaction between Cl- and Ca2+. Of the anions tested, Br- was the most effective in increasing the levels of L-Glu binding. Other effective anions were Cl-, NO3- and formate while F-, HCO3-CIO4-, propionate, SO42- and PO43- were ineffective. The anion specificity was similar to that observed for the Cl- membrane channel, suggesting that this binding site and the ion channel may be related. In the absence of Cl-, Ca2+ has little effect on L-Glu binding. Increasing the Cl- concentration increased the apparent affinity (decreased KCa2+) of the Ca2+-stimulated, L-Glu binding component and also decreased the maximal amount of the enhancement. Conversely, increasing Ca2+ levels increased the maximal enhancement of L-Glu binding brought about by Cl- without affecting the KCl- of the effect. Prior incubation of membranes with Ca2+ did not raise the level of L- Glu binding. Furthermore, EGTA was able to reverse the stimulation of L- Glu binding due to Ca2+. The results indicate that Ca2+ acts ionically to enhance L-Glu binding to rat SPMs.

UR - http://www.scopus.com/inward/record.url?scp=0021683060&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0021683060&partnerID=8YFLogxK

U2 - 10.1016/0024-3205(84)90451-X

DO - 10.1016/0024-3205(84)90451-X

M3 - Article

C2 - 6151108

AN - SCOPUS:0021683060

VL - 35

SP - 2427

EP - 2433

JO - Life Sciences

JF - Life Sciences

SN - 0024-3205

IS - 24

ER -