title: Effect of morphine on aluminium fluoride and dibutyryl-cyclic AMP induced reduction of field potentials in hippocampal slices.
abstract: Effects of morphine and aluminum fluoride on field potentials evoked in hippocampal pyramidal cells were investigated revealing the physiological significance of adenylate cyclase in morphine action. Dibutyryl-cyclic AMP (db-cAMP) reduces the amplitude of potentials, while morphine enhances it. Morphine was without effects on db-cAMP induced reduction of potentials. Aluminum fluoride, known to activate GTP binding proteins, also reduced potentials and this was antagonized by morphine. Furthermore, N-[2-(methylamino)ethyl]-5-isoquinolinesulphonamide dihydrochloride (H-8), a protein kinase A inhibitor, enhanced potentials. When GABA synthesis was inhibited by 3-mercaptopropinoic acid, both morphine and db-cAMP was without effect. These results suggested the inhibition of adenylate cyclase by morphine which might be related with the reduction of GABA release in hippocampal slices.
authors.affiliation: Department of Pharmacology, Faculty of Dentistry, Osaka University, Japan.
authors.forename: Y
authors.initials: Y
authors.lastname: Uchida
authors.forename: S
authors.initials: S
authors.lastname: Maeda
authors.forename: T
authors.initials: T
authors.lastname: Matsuya
authors.forename: K
authors.initials: K
authors.lastname: Saito
mesh_terms: D000262:Adenylyl Cyclases / Q000187:drug effects* / Q000502:physiology; D017607:Aluminum Compounds / Q000494:pharmacology*; D000818:Animals; D003994:Bucladesine / Q000494:pharmacology*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000037:antagonists & inhibitors; D004305:Dose-Response Relationship, Drug; D004558:Electric Stimulation; D005071:Evoked Potentials / Q000187:drug effects; D005459:Fluorides / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects* / Q000502:physiology; D008297:Male; D009020:Morphine / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley
chemical_list: D017607:Aluminum Compounds; D003994:Bucladesine; D009020:Morphine; D017868:Cyclic AMP-Dependent Protein Kinases; D000262:Adenylyl Cyclases; D005459:Fluorides; C032311:aluminum fluoride