The fundamental goal of the proposed research is to elucidate mechanisms of receptor modulation, focussing primarily on the GABA/A receptor of the vertebrate central nervous system. The proposed study has two major parts. First, we propose to extend our preliminary observations that indicate that Ca2+ ions play a fundamental role in modulating the function of the GABA receptor, with the aim of determining the mechanism whereby Ca2+ influences GABA receptor function. In particular, we will confirm or reject a model in which calcium plays a role as an obligatory cofactor in the process of GABA stimulated C1- transport. Secondly, we will carry out electrophysiological and radioligand binding studies to test a theoretical model relating electrophysiological and biochemical parameters of modulator action. In particular, we will determine whether it is possible to predict efficacy of modulators of the GABA response on the basis of binding kinetics. Our long-term goals are to construct molecular models of the interaction of neuromodulators with the GABA/A receptor and to gain an understanding of the molecular underpinnings of GABA/A receptor function. These studies are expected to provide the basis for modeling of the relationship between the GABA receptor and its various modulatory sites, and may yield novel insights into the molecular mechanisms underlying the function of ligand-gated anion channels.

Agency
National Institute of Health (NIH)
Institute
National Institute of Neurological Disorders and Stroke (NINDS)
Type
Research Project (R01)
Project #
5R01NS022116-05
Application #
3404124
Study Section
Neurological Sciences Subcommittee 1 (NLS)
Project Start
1985-04-01
Project End
1993-03-31
Budget Start
1989-04-01
Budget End
1990-03-31
Support Year
5
Fiscal Year
1989
Total Cost
Indirect Cost
Name
Suny Downstate Medical Center
Department
Type
Schools of Medicine
DUNS #
068552207
City
Brooklyn
State
NY
Country
United States
Zip Code
11203
Gyenes, M; Wang, Q; Gibbs, T T et al. (1994) Phosphorylation factors control neurotransmitter and neuromodulator actions at the gamma-aminobutyric acid type A receptor. Mol Pharmacol 46:542-9
Wu, F S; Gibbs, T T; Farb, D H (1993) Dual activation of GABAA and glycine receptors by beta-alanine: inverse modulation by progesterone and 5 alpha-pregnan-3 alpha-ol-20-one. Eur J Pharmacol 246:239-46
Celentano, J J; Gyenes, M; Gibbs, T T et al. (1991) Negative modulation of the gamma-aminobutyric acid response by extracellular zinc. Mol Pharmacol 40:766-73
Wu, F S; Gibbs, T T; Farb, D H (1991) Pregnenolone sulfate: a positive allosteric modulator at the N-methyl-D-aspartate receptor. Mol Pharmacol 40:333-6
Wu, F S; Gibbs, T T; Farb, D H (1990) Inverse modulation of gamma-aminobutyric acid- and glycine-induced currents by progesterone. Mol Pharmacol 37:597-602
Borden, L A; Gibbs, T T (1990) Flunitrazepam photoaffinity labeling of the GABA(A) receptor reduces inhibition of [3H]Ro15-4513 binding by GABA. Eur J Pharmacol 188:391-7
Roca, D J; Rozenberg, I; Farrant, M et al. (1990) Chronic agonist exposure induces down-regulation and allosteric uncoupling of the gamma-aminobutyric acid/benzodiazepine receptor complex. Mol Pharmacol 37:37-43
Roca, D J; Schiller, G D; Friedman, L et al. (1990) gamma-Aminobutyric acidA receptor regulation in culture: altered allosteric interactions following prolonged exposure to benzodiazepines, barbiturates, and methylxanthines. Mol Pharmacol 37:710-9
Czajkowski, C; Farb, D H (1989) Identification of an intracellular pool of gamma-aminobutyric acidA/benzodiazepine receptors en route to the cell surface of brain neurons in culture. Mol Pharmacol 35:183-8
Czajkowski, C; Gibbs, T T; Farb, D H (1989) Transmembrane topology of the gamma-aminobutyric acidA/benzodiazepine receptor: subcellular distribution and allosteric coupling determined in situ. Mol Pharmacol 35:75-84

Showing the most recent 10 out of 15 publications