Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C1323099 (sympathomimetic)
 2,957 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Cumulative concentration-effect curves of oxytocin alone and with various antagonists were obtained in vitro on uteri from estrogen-treated rats. Graded concentrations of salbutamol, isoproterenol, papaverine, theophylline, thioglycollate, and MgCl2 produced a decrease in the maximal effect of oxytocin and a shift of the concentration-effect curves to the right. Salbutamol and isoproterenol appeared to act as functional antagonists of oxytocin in which agonist and antagonist each interacted with its own specific receptor to produce a decreased combined effect on a common effector. Antagonism by papaverine or theophylline was increased by prior or simultaneous treatment with salbutamol, isoproterenol, epinephrine, or norepinephrine. The potentiation had a rapid onset, was partially blocked by propranolol, persisted for at least 85 minutes following washout of salbutamol, and was not due to a residual effect of salbutamol. This interaction could result from phosphodiesterase inhibition by papaverine and the accumulation of higher levels of cyclic 3',5'-adenosine monophosphate brought about by adenyl cyclase activation with the sympathomimetic amines.
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PMID:Antagonism of the uterotonic action of oxytocin in vitro. 111 25