GABAergic mechanisms in morphine-induced hypothermia.
Morphine produced a hypothermic effect in restrained rats which was antagonized by naloxone. This effect was completely inhibited by gamma-acetylenic-GABA, an inhibitor of GABA transaminase and by baclofen, a specific GABAB agonist. Pretreatment with diazepam, an agonist of the benzodiazepine receptor, partially inhibited morphine-induced hypothermia. Flumazenil, a benzodiazepine receptor blocker, potentiated the action of morphine on body temperature. A role of brain GABA in the thermoregulatory effects of morphine is proposed on the basis of these results.
Del Rio-Garcia
J
J
Departamento de Fisiología y Farmacología, Universidad de Murcia, Spain.
Cremades
A
A
D000612:4-Aminobutyrate Transaminase / Q000037:antagonists & inhibitors; D000480:Alkynes; D000614:Aminocaproates / Q000494:pharmacology; D000818:Animals; D001418:Baclofen / Q000494:pharmacology; D001831:Body Temperature / Q000187:drug effects*; D005260:Female; D005442:Flumazenil / Q000494:pharmacology; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains; D005680:gamma-Aminobutyric Acid / Q000502:physiology*
D000480:Alkynes; D000614:Aminocaproates; D005442:Flumazenil; D005680:gamma-Aminobutyric Acid; C013785:4-amino-5-hexynoic acid; D009020:Morphine; D000612:4-Aminobutyrate Transaminase; D001418:Baclofen