title: Naloxone modifies the inotropic decrease induced by halothane on isolated left atria.
abstract: 1. The present study evaluates the interaction between naloxone and halothane on the left atria. 2. Halothane produced significant decrease in auricular inotropism at concentrations ranging from 0.3 to 2.5 v/v%. 3. Naloxone modified the concentration response curve to halothane. The antagonism between both drugs is consistent with a competitive antagonism since the curve obtained had a slope which did not differ significantly from -1. 4. These results suggest that the negative inotropic effects induced by halothane could be mediated by opioid receptors.
authors.affiliation: Department of Physiology and Pharmacology, School of Medicine, Murcia, Spain.
authors.forename: M L
authors.initials: ML
authors.lastname: Laorden
authors.forename: M D
authors.initials: MD
authors.lastname: Carceles
authors.forename: F S
authors.initials: FS
authors.lastname: Miralles
authors.forename: J
authors.initials: J
authors.lastname: Hernandez
mesh_terms: D000818:Animals; D001667:Binding, Competitive / Q000187:drug effects; D004558:Electric Stimulation; D005260:Female; D006221:Halothane / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D006321:Heart / Q000187:drug effects*; D066298:In Vitro Techniques; D008297:Male; D009200:Myocardial Contraction / Q000187:drug effects*; D009270:Naloxone / Q000494:pharmacology*; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D009270:Naloxone; D006221:Halothane