title: Action of steroids on H+ and NH+4 excretion in the toad urinary bladder.
abstract: This study was done to determine if steroid compounds will stimulate the urinary bladder of the toad to increase its capacity to acidify the urine and excrete NH+4. Aldosterone, 17 beta-estradiol, dexamethasone, pregnenolone, and cholesterol were tested on the bladder. All compounds tested were found to stimulate the rate of acidification by the bladder, above that of a paired control hemibladder. In contrast, only the steroids aldosterone and 17 beta-estradiol were found to stimulate NH+4 excretion in the bladder. Cycloheximide was found to block the action of aldosterone on the NH+4 excretion, but did not have a significant effect on the stimulation of acidification by aldosterone. We conclude that steroids stimulate H+ and NH+4 excretion in the toad urinary bladder. In addition, the NH+4 excretory system seems to be more specific to this effect than is the H+ excretory system.
mesh_terms: D000450:Aldosterone / Q000494:pharmacology; D000818:Animals; D002024:Bufo marinus; D002784:Cholesterol / Q000494:pharmacology; D003907:Dexamethasone / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D004958:Estradiol / Q000494:pharmacology; D006859:Hydrogen / Q000378:metabolism*; D008901:Mineralocorticoids / Q000494:pharmacology*; D011284:Pregnenolone / Q000494:pharmacology; D000644:Quaternary Ammonium Compounds / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism; D001743:Urinary Bladder / Q000187:drug effects* / Q000378:metabolism
chemical_list: D008901:Mineralocorticoids; D000644:Quaternary Ammonium Compounds; D000450:Aldosterone; D004958:Estradiol; D011284:Pregnenolone; D003907:Dexamethasone; D006859:Hydrogen; D002784:Cholesterol; D012964:Sodium