title: The effect of theophylline on the responses of the guinea-pig urinary bladder to nerve stimulation, adenosin 5' triphosphate and histamine.
abstract: The effects of theophylline (10(-5)M, 10(-4)M and 10(-3)M) on the contractile responses of the guinea-pig urinary bladder to nerve stimulation, adenosin 5' triphosphate (ATP) and histamine have been investigated. Contractile responses were unaffected by 10(-5)M and 10(-4)M therophylline but were significantly reduced by 10(-3)M theophylline. Since responses to histamine were reduced to a similar extent as responses to ATP, it is suggested that theophylline is not a specific antagonist of ATP in this tissue and that the ATP receptors in the bladder differ from those in other smooth muscle preparations.
mesh_terms: D000255:Adenosine Triphosphate / Q000494:pharmacology*; D000818:Animals; D004347:Drug Interactions; D004558:Electric Stimulation; D005260:Female; D006168:Guinea Pigs; D006632:Histamine / Q000494:pharmacology*; D066298:In Vitro Techniques; D009119:Muscle Contraction / Q000187:drug effects; D009130:Muscle, Smooth / Q000187:drug effects; D013806:Theophylline / Q000494:pharmacology*; D001743:Urinary Bladder / Q000187:drug effects* / Q000294:innervation
chemical_list: D006632:Histamine; D000255:Adenosine Triphosphate; D013806:Theophylline