GABA-induced /sup 36/Cl/sup -/ influx: a biochemical correlate of the physiological event regulated by GABA receptors

Conference · Wed Mar 05 04:00:00 EST 1986 · Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States)

OSTI ID:6898893

Gant, D; Ramadan, A; Eldefrawi, A; Eldefrawi, M

Microsacs from whole rat brain were prepared in HEPES-buffered saline, as described by Harris and Allan. GABA-induced /sup 36/Cl/sup -/ influx into brain microsacs at 30/sup 0/C was dose dependent, saturable, and had an ED/sub 50/ of 25 ..mu..M. The Hill coefficient of the dose-response curve of the GABA response was >1. Other GABA agonists induced /sup 36/Cl/sup -/ influx similarly and with a rank order that paralleled their physiological potencies. Preincubation with GABA produced receptor desensitization and reduced the influx. Bicuculline inhibited the GABA-induced influx competitively, and the inhibition was stereospecific ((+)bicuculline was >10-fold more effective than (-)bicuculline). The convulsants picrotoxinin and t-butyl-bicyclophosphorothionate also inhibited to GABA-induced /sup 36/Cl/sup -/ influx, but noncompetitively. The same effect was observed with cyclodiene insecticides, and their action was stereospecific. Pentobarbital, on the other hand, potentiated the GABA-induced /sup 36/Cl/sup -/ influx.

• Research Organization: Univ. of Maryland School of Medicine, Baltimore
• OSTI ID: 6898893
• Report Number(s): CONF-8604222-
• Conference Information: Journal Name: Fed. Proc., Fed. Am. Soc. Exp. Biol.; (United States) Journal Volume: 45:4
• Country of Publication: United States
• Language: English

Related Subjects

550201* -- Biochemistry-- Tracer Techniques
59 BASIC BIOLOGICAL SCIENCES
AMINO ACIDS
AMINOBUTYRIC ACID
ANIMALS
AUTONOMIC NERVOUS SYSTEM AGENTS
BETA DECAY RADIOISOTOPES
BETA-MINUS DECAY RADIOISOTOPES
BIOCHEMICAL REACTION KINETICS
BODY
BRAIN
CARBOXYLIC ACIDS
CENTRAL NERVOUS SYSTEM
CHLORINE 36
CHLORINE COMPOUNDS
CHLORINE ISOTOPES
DOSE-RESPONSE RELATIONSHIPS
DRUGS
ELECTRON CAPTURE RADIOISOTOPES
HALOGEN COMPOUNDS
INHIBITION
ISOTOPE APPLICATIONS
ISOTOPES
KINETICS
LIGHT NUCLEI
MAMMALS
MEMBRANE PROTEINS
MEMBRANE TRANSPORT
NERVOUS SYSTEM
NEUROREGULATORS
NUCLEI
ODD-ODD NUCLEI
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANS
PROTEINS
RADIOISOTOPES
RATS
REACTION KINETICS
RECEPTORS
RESPONSE MODIFYING FACTORS
RODENTS
TRACER TECHNIQUES
VERTEBRATES
YEARS LIVING RADIOISOTOPES