Potentiation of beta-sympathomimetics with alpha-adrenoceptor blocking drugs in guinea pig trachea and human bronchus preparations.
The actions of beta-sympathomimetics alone and in various combinations with alpha-adrenoceptor blocking agents were studied in guinea pig tracheal chain and in some preparations of human bronchi taken in operations. All the alpha-adrenoceptor blockers caused 50-100% potentiation of the effects of the beta-sympathomimetics studied in both preparations, had no effects of their own in the rather low concentrations used (10(-10) --10(-6) mol/l). The results show that guinea pig and human tracheobronchial smooth muscle react similarly to these drugs and may contain adrenergic alpha-receptors.
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology*; D000318:Adrenergic beta-Agonists / Q000494:pharmacology*; D000420:Albuterol / Q000494:pharmacology; D000818:Animals; D001980:Bronchi / Q000187:drug effects* / Q000294:innervation; D004088:Dihydroergotoxine / Q000494:pharmacology; D004357:Drug Synergism; D005260:Female; D006168:Guinea Pigs; D006801:Humans; D007545:Isoproterenol / Q000494:pharmacology*; D008297:Male; D013948:Moxisylyte / Q000494:pharmacology; D010643:Phenoxybenzamine / Q000494:pharmacology; D010646:Phentolamine / Q000494:pharmacology; D011942:Receptors, Adrenergic, alpha / Q000502:physiology; D013726:Terbutaline / Q000494:pharmacology; D014132:Trachea / Q000187:drug effects* / Q000294:innervation
D000317:Adrenergic alpha-Antagonists; D000318:Adrenergic beta-Agonists; D011942:Receptors, Adrenergic, alpha; D010643:Phenoxybenzamine; D004088:Dihydroergotoxine; D007545:Isoproterenol; D013726:Terbutaline; D013948:Moxisylyte; D000420:Albuterol; D010646:Phentolamine