title: Relaxation of isolated aorta of the rabbit by picolinic acids.
abstract: 1 When the isolated thoracic aorta of the rabbit was contracted with prostaglandin F2alpha, 5-alkylpicolinic acids produced dose-dependent relaxations. 2 Picolinic acid, 2,5-pyridinedicarboxylic acid and 5-acetylpicolinic acid which do not have the 5-alkyl residue failed to relax blood vessels. 3 The vascular relaxation was dependent on the number of carbon atoms in the 5-alkyl compounds. 4 Relaxations which occurred with 5-alkylpicolinic acids were not affected by pretreatment with either propranolol or atropine. 5 It is concluded that the 5-alkyl residue is necessary for the vascular relaxation with 5-alkylpicolinic acid and that it was not produced by stimulation of beta-adrenoceptors or cholinoceptors but rather through an activation of the basic process.
mesh_terms: D000628:Aminophylline / Q000494:pharmacology; D000818:Animals; D001013:Aorta, Thoracic / Q000187:drug effects; D001285:Atropine / Q000494:pharmacology; D001808:Blood Vessels / Q000187:drug effects*; D002264:Carboxylic Acids / Q000494:pharmacology; D003998:Dicarboxylic Acids / Q000494:pharmacology; D004347:Drug Interactions; D005260:Female; D006220:Haloperidol / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009126:Muscle Relaxation / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects*; D010042:Ouabain / Q000494:pharmacology; D010848:Picolinic Acids / Q000494:pharmacology*; D011433:Propranolol / Q000494:pharmacology; D011460:Prostaglandins F / Q000494:pharmacology; D011725:Pyridines / Q000494:pharmacology; D011817:Rabbits; D013329:Structure-Activity Relationship
chemical_list: D002264:Carboxylic Acids; D003998:Dicarboxylic Acids; D010848:Picolinic Acids; D011460:Prostaglandins F; D011725:Pyridines; D000628:Aminophylline; D010042:Ouabain; D001285:Atropine; D011433:Propranolol; D006220:Haloperidol