Article date: 1991/4/1
PubMed ID: 2018109
Journal name: The American journal of physiology (ISSN: 0002-9513)
The gamma-aminobutyric acid (GABA)-induced macroscopic Cl- current (ICl) was investigated in acutely isolated nucleus tractus solitarii (NTS) neurons by a conventional patch-clamp technique combined with a rapid drug application method. The GABA- and muscimol-induced ICl increased in a concentration-dependent manner. The reversal potentials were close to the Cl- equilibrium potential. Pentobarbital sodium (PB) itself elicited a current. Bicuculline (BIC), strychnine (STR), picrotoxin, benzylpenicillin (PCG), Cd2+, and Zn2+ suppressed the GABA response in a concentration-dependent manner. Both BIC and STR shifted the concentration-response curve for GABA response to the right, whereas PCG suppressed the maximum response without affecting the threshold, indicating that BIC and STR antagonized competitively and PCG noncompetitively. The inhibitory action of PCG on GABA response was in a highly voltage-dependent manner. PB shifted the concentration-response curve for GABA response to the left. The augmentatory effect of PB was voltage dependent.
Author List: Nakagawa T, Wakamori M, Shirasaki T, Nakaye T, Akaike N
Publication Types: Journal Article; Research Support, Non-U.S. Gov't
Substances mentioned in the article: Picrotoxin; Muscimol; gamma-Aminobutyric Acid; Strychnine; Pentobarbital; Penicillin G; Bicuculline;
Mesh terms: Animals; Bicuculline/pharmacology; In Vitro Techniques; Kinetics; Medulla Oblongata/physiology; Membrane Potentials/drug effects; Muscimol/pharmacology; Neurons/drug effects; Penicillin G/pharmacology; Pentobarbital/pharmacology; Picrotoxin/pharmacology; Rats; Rats, Inbred Strains; Strychnine/pharmacology; gamma-Aminobutyric Acid/pharmacology;