title: Carbon dioxide inhalation, stress and anxiogenic drugs reduce the function of GABAA receptor complex in the rat brain.
abstract: 1. The effect of different stressful stimuli on the function of the GABAA-ionophore receptor complex was evaluated by measuring the binding of 35S-TBPS to the chloride channel associated recognition sites. 2. Foot-shock stress enhanced 35S-TBPS binding in membrane preparation from rat cerebral cortex. The effect of foot-shock on 35S-TBPS binding was mimicked by the anxiogenic and proconvulsant beta-carboline FG 7142 and antagonized by anxiolytic benzodiazepines and by the novel anxiolytic and anticonvulsant beta-carboline, abecarnil. 3. A brief exposure of rats to CO2 inhalation produced, like foot-shock and FG 7142, a marked increase of 35S-TBPS binding in the cerebral cortex, cerebellum and hippocampus. The effect of CO2 inhalation was maximal 10 min after treatment and return to control value in 2 hours. Previous administration of anxiolytic drugs (alprazolam and abecarnil) completely prevented the CO2 inhalation-induced increase of 35S-TBPS binding. 4. All together these data strongly suggest that carbon dioxide inhalation, like stress and anxiogenic drugs, decreases the function of the GABAA receptor complex.
authors.affiliation: Department of Experimental Biology, University of Cagliari, Italy.
authors.forename: A
authors.initials: A
authors.lastname: Concas
authors.forename: E
authors.initials: E
authors.lastname: Sanna
authors.forename: T
authors.initials: T
authors.lastname: Cuccheddu
authors.forename: M P
authors.initials: MP
authors.lastname: Mascia
authors.forename: G
authors.initials: G
authors.lastname: Santoro
authors.forename: E
authors.initials: E
authors.lastname: Maciocco
authors.forename: G
authors.initials: G
authors.lastname: Biggio
mesh_terms: D000280:Administration, Inhalation; D000818:Animals; D014151:Anti-Anxiety Agents / Q000494:pharmacology; D001007:Anxiety / Q000139:chemically induced / Q000378:metabolism*; D001569:Benzodiazepines; D001923:Brain Chemistry / Q000187:drug effects / Q000502:physiology*; D001643:Bridged Bicyclo Compounds / Q000378:metabolism; D019086:Bridged Bicyclo Compounds, Heterocyclic; D002243:Carbolines / Q000494:pharmacology; D002245:Carbon Dioxide / Q000008:administration & dosage / Q000494:pharmacology*; D002531:Cerebellum / Q000187:drug effects / Q000378:metabolism; D002540:Cerebral Cortex / Q000187:drug effects / Q000378:metabolism; D018118:Chloride Channels; D004597:Electroshock; D006624:Hippocampus / Q000187:drug effects / Q000378:metabolism; D007473:Ion Channels / Q000187:drug effects / Q000378:metabolism; D008297:Male; D008565:Membrane Proteins / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D017207:Rats, Sprague-Dawley; D011963:Receptors, GABA-A / Q000187:drug effects / Q000378:metabolism*; D013315:Stress, Psychological / Q000378:metabolism*
chemical_list: D014151:Anti-Anxiety Agents; D001643:Bridged Bicyclo Compounds; D019086:Bridged Bicyclo Compounds, Heterocyclic; D002243:Carbolines; D018118:Chloride Channels; D007473:Ion Channels; D008565:Membrane Proteins; D011963:Receptors, GABA-A; D001569:Benzodiazepines; D002245:Carbon Dioxide; C035874:FG 7142; C037476:tert-butylbicyclophosphorothionate