Potentiation by ethanol of GABA-induced current and facilitation of its desensitization in cultured rat cortical neurons.
1. Patch-clamp whole cell recording was performed to elucidate whether or not ethanol, at low concentration, has an effect on the GABAA receptor in cultured rat cortical neurons as compared with flunitrazepam. 2. Bath application of ethanol (0.01%) or flunitrazepam (1 mM) potentiated the peak amplitude of GABA-induced (10 microM) current without affecting the equilibrium potential. 3. The decay time constant and time to peak of GABA-induced current were shortened in the presence of ethanol or flunitrazepam. 4. These findings indicate that a low concentration of ethanol and flunitrazepam potentiates the GABA-induced current concomitantly with acceleration of desensitization to the drug.
Tsujiyama
S
S
Department of Pharmacology, Hiroshima University School of Medicine, Japan.
Akaike
A
A
Ujihara
H
H
Sasa
M
M
D000818:Animals; D002478:Cells, Cultured; D002492:Central Nervous System Depressants / Q000494:pharmacology*; D002540:Cerebral Cortex / Q000187:drug effects* / Q000502:physiology; D004357:Drug Synergism; D000431:Ethanol / Q000494:pharmacology*; D005445:Flunitrazepam / Q000494:pharmacology*; D018757:GABA Modulators / Q000494:pharmacology*; D009474:Neurons / Q000187:drug effects; D018408:Patch-Clamp Techniques; D051381:Rats; D017208:Rats, Wistar; D011963:Receptors, GABA-A / Q000187:drug effects / Q000502:physiology; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology*
D002492:Central Nervous System Depressants; D018757:GABA Modulators; D011963:Receptors, GABA-A; D000431:Ethanol; D005680:gamma-Aminobutyric Acid; D005445:Flunitrazepam