title: ANP-stimulated cGMP egression in renal principal cells: abrogation of polarity by SV40 large T.
abstract: Egression of atrial natriuretic peptide (ANP)-stimulated guanosine 3', 5'-cyclic monophosphate (cGMP) was compared with that of isoproterenol-stimulated adenosine 3', 5'-cyclic monophosphate (cAMP) in a rabbit collecting duct cell line transformed with a temperature-sensitive strain of simian virus 40 (SV40). At 39.5 degrees C (inactivated large T), cells exhibit major features of principal cells, whereas at 33 degrees C (functional large T) they lose most of their specific properties. When cells were grown on plastic at 39.5 degrees C, both cyclic nucleotides were predominantly released extracellularly via probenecid-sensitive carriers. Probenecid (3mM) reduced the ratios of extracellular cGMP and cAMP by 84 and 70%, respectively. The amount of extracellular cGMP or cAMP ws linearly correlated with the time integral of the intracellular cyclic nucleotide, suggesting first-order kinetics. The apparent first-order rate constant (k) was sixfold greater for cGMP (0.139 +/- 0.037 min-1, n = 3 experiments) than for cAMP (0.022 +/- 0.003(-1), n = 3 experiments). 3-Isobutyl-1-methylxanthine markedly inhibited extrusion of cGMP (k = 0.022 +/- 0.003 min-1), whereas that of cAMP was unchanged. When cells were grown on filters at 39.5 degrees C, both nucleotides were predominantly released in the apical medium but with a greater polarity for cGMP (83 +/- 4%, n = 6 experiments) than for cAMP (60 +/- 6%, n = 3 experiments) and a prevailing apical localization of the probenecid-sensitive carrier. Activation of SV40 large T at 33 degrees C did not alter cyclic nucleotide transport characteristics but abolished the polarity of probenecid-sensitive cyclic nucleotide extrusion. These results suggest a physiological role for luminal cGMP in the rabbit collecting duct and a specific effect of large T on the probenecid-sensitive carrier polarity.
authors.affiliation: Institut National de la Santé et de la Recherche Médicale Unité 64, Hôpital Tenon, Paris, France.
authors.forename: V
authors.initials: V
authors.lastname: Millul
authors.forename: D
authors.initials: D
authors.lastname: Prié
authors.forename: M
authors.initials: M
authors.lastname: Géniteau-Legendre
authors.forename: M C
authors.initials: MC
authors.lastname: Verpont
authors.forename: B
authors.initials: B
authors.lastname: Baudouin
authors.forename: P M
authors.initials: PM
authors.lastname: Ronco
mesh_terms: D015056:1-Methyl-3-isobutylxanthine / Q000494:pharmacology; D000818:Animals; D000952:Antigens, Polyomavirus Transforming / Q000494:pharmacology*; D009320:Atrial Natriuretic Factor / Q000494:pharmacology*; D002461:Cell Line, Transformed; D016764:Cell Polarity / Q000187:drug effects*; D000242:Cyclic AMP / Q000378:metabolism; D006152:Cyclic GMP / Q000378:metabolism*; D007545:Isoproterenol / Q000494:pharmacology; D007685:Kidney Tubules, Collecting / Q000166:cytology / Q000378:metabolism*; D011339:Probenecid / Q000494:pharmacology; D011817:Rabbits
chemical_list: D000952:Antigens, Polyomavirus Transforming; D009320:Atrial Natriuretic Factor; D000242:Cyclic AMP; D006152:Cyclic GMP; D007545:Isoproterenol; D011339:Probenecid; D015056:1-Methyl-3-isobutylxanthine