Vasopressin V1 receptors on the principal cells of the rabbit cortical collecting tubule. Stimulation of cytosolic free calcium and inositol phosphate production via coupling to a pertussis toxin substrate.
The effects of arginine vasopressin (AVP) on the cytosolic free calcium concentration ([Ca2+]f) were examined in freshly immunodissected rabbit cortical collecting tubule cells using fluorescent Ca2+ indicators fura-2 and indo-1. The addition of AVP to a cell suspension resulted in a rapid and transient increase in the [Ca2+]f. The 1-deamino-8-D-AVP (dDVP), a V2 receptor agonist of AVP that stimulated adenosine 3',5' cAMP production in these cells, had no effect on [Ca2+]f and did not affect AVP-induced increase in [Ca2+]f. The AVP-induced increase in [Ca2+]f but not cAMP production was blocked by the V1 receptor antagonist, [1-(beta-mercapto-beta-beta-cyclopentamethylene propionic acid), 2-(O-methyl)tyrosine] Arg8-vasopressin. The AVP-stimulated increase in [Ca2+]f appeared to be largely due to Ca2+ release from intracellular stores as reduction of extracellular Ca2+ with EGTA had little if any effect on the AVP-induced increase in [Ca2+]f. This AVP-induced increase in [Ca2+]f was associated with an increase in inositol-1,4,5-trisphosphate production and appeared to involve a guanine nucleotide-binding protein (G), since the pretreatment of cells with pertussis toxin for 4-6 h inhibited this effect. Finally, measurements of [Ca2+]f in single cells suggest that only the principal cells of the collecting tubules respond to AVP with an increase in [Ca2+]f. In summary, these results demonstrate that the principal cells of the cortical collecting tubule possess two distinct receptor systems for vasopressin, the well-known V2 receptor coupled to adenylate cyclase, and a V1 receptor system that leads to the mobilization of cytosolic calcium, coupled through a pertussis toxin substrate (G protein) to a production of inositol phosphates.
Burnatowska-Hledin
M A
MA
Department of Physiology, Michigan State University, East Lansing 48824.
Spielman
W S
WS
D037361:Adenylate Cyclase Toxin; D000818:Animals; D001127:Arginine Vasopressin / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D000242:Cyclic AMP / Q000096:biosynthesis; D003600:Cytosol / Q000378:metabolism; D019204:GTP-Binding Proteins / Q000378:metabolism; D007295:Inositol Phosphates / Q000096:biosynthesis*; D007684:Kidney Tubules / Q000378:metabolism*; D007685:Kidney Tubules, Collecting / Q000378:metabolism*; D037342:Pertussis Toxin; D011817:Rabbits; D011945:Receptors, Angiotensin / Q000378:metabolism*; D017483:Receptors, Vasopressin; D013403:Sugar Phosphates / Q000096:biosynthesis*; D010566:Virulence Factors, Bordetella / Q000378:metabolism*
D037361:Adenylate Cyclase Toxin; D007295:Inositol Phosphates; D011945:Receptors, Angiotensin; D017483:Receptors, Vasopressin; D013403:Sugar Phosphates; D010566:Virulence Factors, Bordetella; D001127:Arginine Vasopressin; D000242:Cyclic AMP; D037342:Pertussis Toxin; D019204:GTP-Binding Proteins; D002118:Calcium