title: Relaxant activity of three aporphine alkaloids from Annona cherimolia on isolated aorta of rat.
abstract: In the present study we tested the relaxant effect of three aporphine alkaloids--roemerine, anonaine and dehydroroemerine--isolated from the roots of Annona cherimolia, on isolated strips of rat thoracic aorta. All compounds completely relaxed KCl- and noradrenaline-induced contractions with different potencies depending on their structural characteristics. The experiments, carried out in Ca(2+)-free medium using two different agonists (noradrenaline and caffeine) which mobilize calcium intracellularly by different mechanisms of action, showed that the alkaloids made no contribution to intracellular calcium processes. The present study provides evidence that the relaxant effects produced by aporphine alkaloids may be due to the blockade of calcium movements across the cell membrane, mainly through voltage-operated channels, and to the disruption of alpha 1-adrenoceptors connected to receptor-operated channels.
authors.affiliation: Departamento de Farmacologia, Facultad de Farmacia, Universidad de Valencia, Spain.
authors.forename: S
authors.initials: S
authors.lastname: Chuliá
authors.forename: M D
authors.initials: MD
authors.lastname: Ivorra
authors.forename: A
authors.initials: A
authors.lastname: Cavé
authors.forename: D
authors.initials: D
authors.lastname: Cortés
authors.forename: M A
authors.initials: MA
authors.lastname: Noguera
authors.forename: M P
authors.initials: MP
authors.lastname: D'Ocón
mesh_terms: D000470:Alkaloids / Q000494:pharmacology; D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001013:Aorta, Thoracic / Q000187:drug effects* / Q000502:physiology; D001060:Aporphines; D002118:Calcium / Q000378:metabolism; D002121:Calcium Channel Blockers / Q000494:pharmacology; D004110:Diltiazem / Q000494:pharmacology; D004149:Dioxoles / Q000494:pharmacology; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D007546:Isoquinolines / Q000494:pharmacology; D016859:Lipoxygenase Inhibitors / Q000494:pharmacology*; D008297:Male; D009126:Muscle Relaxation / Q000187:drug effects; D009131:Muscle, Smooth, Vascular / Q000187:drug effects*; D009543:Nifedipine / Q000494:pharmacology; D009638:Norepinephrine / Q000494:pharmacology; D011189:Potassium Chloride / Q000494:pharmacology; D011224:Prazosin / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013565:Sympatholytics / Q000494:pharmacology
chemical_list: D000470:Alkaloids; D000975:Antioxidants; D001060:Aporphines; D002121:Calcium Channel Blockers; D004149:Dioxoles; D004365:Drugs, Chinese Herbal; D007546:Isoquinolines; D016859:Lipoxygenase Inhibitors; D013565:Sympatholytics; C098138:anonaine; C030170:dehydroroemerine; C030169:roemerine; D011189:Potassium Chloride; D004110:Diltiazem; D009543:Nifedipine; D002118:Calcium; D009638:Norepinephrine; D011224:Prazosin