[Ca2+ participation on the outer surface of the apical membrane of the bladder epithelial cells in the frog in the reaction to antidiuretic hormone].
The ADH effect on the osmotic permeability was studied in experiments on isolated frog urinary bladders. The absence of Ca2+ in the hypotonic solution on the side of the bladder mucous membrane and an increase of its concentration from 0.23 to 11.7 mM/1 did not change the response to the ADH. The removal of Ca2+ from the apical membrane after adding 10(-3) M of EGTA to the mucous membrane solution resulted in an abrupt decrease of cell capabilities to react to the ADH. Ca channel blockers (verapamil, cobalt and nickel ions in 10(-4) M) in the apical plasmic membrane solution lovered the cell response to the ADH. The data obtained indicate that the presence of Ca2+ on the outer surface of the apical plasmic membrane is necessary for the ADH action.
D000818:Animals; D002118:Calcium / Q000502:physiology*; D002121:Calcium Channel Blockers / Q000494:pharmacology; D002463:Cell Membrane Permeability / Q000187:drug effects; D004533:Egtazic Acid / Q000494:pharmacology; D004848:Epithelium / Q000187:drug effects; D066298:In Vitro Techniques; D007552:Isotonic Solutions; D011896:Rana temporaria; D000077331:Ringer's Solution; D012704:Serous Membrane / Q000187:drug effects; D001743:Urinary Bladder / Q000187:drug effects*; D014667:Vasopressins / Q000494:pharmacology*
D002121:Calcium Channel Blockers; D007552:Isotonic Solutions; D014667:Vasopressins; D004533:Egtazic Acid; D000077331:Ringer's Solution; D002118:Calcium
Uchastie Ca2+ na vneshneĭ poverkhnosti apikal'noĭ membrany kletok épiteliia mochevogo puzyria liagushki v reaktsii na antidiureticheskiĭ gormon.