The effect of catecholamines on H+ and NH+4 excretion in toad urinary bladder.
The catecholamines epinephrine and norepinephrine, when placed on the toad urinary bladder in vitro, at a final concentration of 50 microM, caused a significant increase in H+ and NH+4 excretion by the bladder. Isoprenaline in a final concentration of 50 microM also increased H+ and NH+4 excretion in the bladder. Propranolol at a concentration of 50 microM blocked the stimulation of H+ excretion by isoprenaline but propranolol at 100 microM was required to block the stimulation of NH+4 by isoprenaline. The dose-response analysis indicates that the concentration of epinephrine used (50 microM) is at or near the maximal effective dose. These findings indicate that catecholamines stimulate H+ and NH+4 excretion in the toad urinary bladder and evidence suggests this may be mediated via the beta receptor mechanism.
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000319:Adrenergic beta-Antagonists / Q000494:pharmacology; D000818:Animals; D002024:Bufo marinus; D002395:Catecholamines / Q000494:pharmacology*; D004837:Epinephrine / Q000494:pharmacology; D006859:Hydrogen / Q000652:urine*; D066298:In Vitro Techniques; D007545:Isoproterenol / Q000494:pharmacology; D009638:Norepinephrine / Q000494:pharmacology; D000644:Quaternary Ammonium Compounds / Q000652:urine*; D001743:Urinary Bladder / Q000378:metabolism*
D000317:Adrenergic alpha-Antagonists; D000319:Adrenergic beta-Antagonists; D002395:Catecholamines; D000644:Quaternary Ammonium Compounds; D006859:Hydrogen; D007545:Isoproterenol; D009638:Norepinephrine; D004837:Epinephrine