title: Control of renin secretion from rat juxtaglomerular cells by cAMP-specific phosphodiesterases.
abstract: We tested the hypothesis that cGMP stimulates renin release through inhibition of the cAMP-specific phosphodiesterase 3 (PDE3) in isolated rat juxtaglomerular (JG) cells. In addition, we assessed the involvement of PDE4 in JG-cell function. JG cells expressed PDE3A and PDE3B, and the PDE3 inhibitor trequinsin increased cellular cAMP content, enhanced forskolin-induced cAMP formation, and stimulated renin release from incubated and superfused JG cells. Trequinsin-mediated stimulation of renin release was inhibited by the permeable protein kinase A antagonist Rp-8-CPT-cAMPS. PDE4C was also expressed, and the PDE4 inhibitor rolipram enhanced cellular cAMP content. Dialysis of single JG cells with cAMP in whole-cell patch-clamp experiments led to concentration-dependent, biphasic changes in cell membrane capacitance (C(m)) with a marked increase in C(m) at 1 micromol/L, no net change at 10 micromol/L, and a decrease at 100 micromol/L cAMP. cGMP also had a dual effect on C(m) at 10-fold higher concentration compared with cAMP. Trequinsin, milrinone, and rolipram mimicked the effect of cAMP on C(m). Trequinsin, cAMP, and cGMP enhanced outward current 2- to 3-fold at positive membrane potentials. The effects of cAMP, cGMP, and trequinsin on C(m) and cell currents were abolished by inhibition of protein kinase A with Rp-cAMPs. We conclude that degradation of cAMP by PDE3 and PDE4 contributes to regulation of renin release from JG cells. Our data provide evidence at the cellular level that stimulation of renin release by cGMP involves inhibition of PDE3 resulting in enhanced cAMP formation and activation of the cAMP sensitive protein kinase.
authors.affiliation: Department of Physiology and Pharmacology, University of Southern Denmark, Odense, Denmark. friis@imbmed.sdu.dk
authors.forename: Ulla G
authors.initials: UG
authors.lastname: Friis
authors.forename: Boye L
authors.initials: BL
authors.lastname: Jensen
authors.forename: Shala
authors.initials: S
authors.lastname: Sethi
authors.forename: Ditte
authors.initials: D
authors.lastname: Andreasen
authors.forename: Pernille B
authors.initials: PB
authors.lastname: Hansen
authors.forename: Ole
authors.initials: O
authors.lastname: Skøtt
mesh_terms: D015105:3',5'-Cyclic-AMP Phosphodiesterases / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D005576:Colforsin / Q000494:pharmacology; D000242:Cyclic AMP / Q000031:analogs & derivatives* / Q000378:metabolism / Q000494:pharmacology*; D017868:Cyclic AMP-Dependent Protein Kinases / Q000378:metabolism; D006152:Cyclic GMP / Q000494:pharmacology; D054684:Cyclic Nucleotide Phosphodiesterases, Type 3; D054703:Cyclic Nucleotide Phosphodiesterases, Type 4; D007545:Isoproterenol / Q000494:pharmacology; D007546:Isoquinolines / Q000494:pharmacology; D007606:Juxtaglomerular Apparatus / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D008564:Membrane Potentials / Q000187:drug effects; D051379:Mice; D018408:Patch-Clamp Techniques; D051381:Rats; D017207:Rats, Sprague-Dawley; D012083:Renin / Q000378:metabolism*; D044005:Tetrahydroisoquinolines; D013873:Thionucleotides / Q000494:pharmacology
chemical_list: D007546:Isoquinolines; D044005:Tetrahydroisoquinolines; D013873:Thionucleotides; D005576:Colforsin; C015929:8-((4-chlorophenyl)thio)cyclic-3',5'-AMP; C035964:trequinsin; D000242:Cyclic AMP; D017868:Cyclic AMP-Dependent Protein Kinases; D015105:3',5'-Cyclic-AMP Phosphodiesterases; D054684:Cyclic Nucleotide Phosphodiesterases, Type 3; D054703:Cyclic Nucleotide Phosphodiesterases, Type 4; C517289:Pde3a protein, mouse; C517290:Pde3a protein, rat; C517293:Pde3b protein, mouse; C517294:Pde3b protein, rat; D012083:Renin; D006152:Cyclic GMP; D007545:Isoproterenol