Effects of parathyroid hormone on H+ and NH+4 excretion in toad urinary bladder.
The urinary bladder of Bufo marinus excretes H+ and NH+4, and the H+ excretion is increased after the animal is placed in metabolic acidosis. The present study was done to determine if parathyroid hormone could stimulate the bladder to increase the excretion of H+ and/or NH+4. Parathyroid hormone added to the serosal solution in a final concentration of 10 mug/ml was found to increase H+ excretion by 50 per cent above the control hemibladders, while there was no effect on NH+4 excretion. Parathyroid hormone had no effect on H+ excretion when added to the mucosal solution. We also performed experiments utilizing theophylline and dibutyryl cyclic AMP which mimicked those of the parathyroid hormone experiments. A dose-response analysis was performed and the results indicate that 1 mug/ml of parathyroid hormone was the minimal effective dose. These results suggest that parathyroid hormone can stimulate H+ excretion in the toad urinary bladder and this effect seems to be mediated by cyclic AMP. In addition, it was found that parathyroid hormone has no effect on NH+4 excretion.
D000641:Ammonia / Q000652:urine*; D000818:Animals; D003994:Bucladesine / Q000494:pharmacology; D002024:Bufo marinus; D004305:Dose-Response Relationship, Drug; D006859:Hydrogen / Q000652:urine*; D006863:Hydrogen-Ion Concentration; D010281:Parathyroid Hormone / Q000494:pharmacology*; D013806:Theophylline / Q000494:pharmacology; D001743:Urinary Bladder / Q000187:drug effects / Q000378:metabolism*
D010281:Parathyroid Hormone; D003994:Bucladesine; D000641:Ammonia; D006859:Hydrogen; D013806:Theophylline