Cellular origin and hormonal regulation of K(+)-ATPase activities sensitive to Sch-28080 in rat collecting duct.
Rat collecting ducts exhibit type I or type III K(+)-ATPase activities when animals are fed a normal (NK) or a K(+)-depleted diet (LK). This study aimed at determining functionally the cell origin of these two K(+)-ATPases. For this purpose, we searched for an effect on K(+)-ATPases of hormones that trigger cAMP production in a cell-specific fashion. The effects of 1-deamino-8-D-arginine vasopressin (dD-AVP), calcitonin, and isoproterenol in principal cells, alpha-intercalated cells, and beta-intercalated cells of cortical collecting duct (CCD), respectively, and of dD-AVP and glucagon in principal and alpha-intercalated cells of outer medullary collecting duct (OMCD), respectively, were examined. In CCDs, K(+)-ATPase was stimulated by calcitonin and isoproterenol in NK rats (type I K(+)-ATPase) and by dD-AVP in LK rats (type III K(+)-ATPase). In OMCDs, dD-AVP and glucagon stimulated type III but not type I K(+)-ATPase. These hormone effects were mimicked by the cAMP-permeant analog dibutyryl-cAMP. In conclusion, in NK rats, cAMP stimulates type I K(+)-ATPase activity in alpha- and beta-intercalated CCD cells, whereas in LK rats it stimulates type III K(+)-ATPase in principal cells of both CCD and OMCD and in OMCD intercalated cells.
Laroche-Joubert
N
N
Laboratoire de Biologie Intégrée des Cellules Rénales, Service de Biologie Cellulaire, Commissariat à l'Energie Atomique, Saclay, Unité de Recherche Associée 1859, Centre National de la Recherche Scientifique, 91191 Gif-sur-Yvette Cedex, France.
Marsy
S
S
Doucet
A
A
D000251:Adenosine Triphosphatases / Q000037:antagonists & inhibitors* / Q000378:metabolism*; D000818:Animals; D027682:Cation Transport Proteins; D003894:Deamino Arginine Vasopressin / Q000494:pharmacology; D004791:Enzyme Inhibitors / Q000494:pharmacology*; D005934:Glucagon / Q000378:metabolism; D006728:Hormones / Q000494:pharmacology*; D007093:Imidazoles / Q000494:pharmacology*; D007685:Kidney Tubules, Collecting / Q000166:cytology* / Q000187:drug effects / Q000201:enzymology*; D008297:Male; D011191:Potassium Deficiency / Q000201:enzymology; D051381:Rats; D017207:Rats, Sprague-Dawley; D012413:Rubidium / Q000378:metabolism
D027682:Cation Transport Proteins; D004791:Enzyme Inhibitors; D006728:Hormones; D007093:Imidazoles; C035235:Sch 28080; D005934:Glucagon; D000251:Adenosine Triphosphatases; C022761:potassium transporting ATPase; D003894:Deamino Arginine Vasopressin; D012413:Rubidium