title: cGMP catabolism by phosphodiesterase 5A regulates cardiac adrenergic stimulation by NOS3-dependent mechanism.
abstract: Beta-adrenergic agonists stimulate cardiac contractility and simultaneously blunt this response by coactivating NO synthase (NOS3) to enhance cGMP synthesis and activate protein kinase G (PKG-1). cGMP is also catabolically regulated by phosphodiesterase 5A (PDE5A). PDE5A inhibition by sildenafil (Viagra) increases cGMP and is used widely to treat erectile dysfunction; however, its role in the heart and its interaction with beta-adrenergic and NOS3/cGMP stimulation is largely unknown. In nontransgenic (control) murine in vivo hearts and isolated myocytes, PDE5A inhibition (sildenafil) minimally altered rest function. However, when the hearts or isolated myocytes were stimulated with isoproterenol, PDE5A inhibition was associated with a suppression of contractility that was coupled to elevated cGMP and increased PKG-1 activity. In contrast, NOS3-null hearts or controls with NOS inhibited by N(G)-nitro-L-arginine methyl ester, or soluble guanylate cyclase (sGC) inhibited by 1H-[1,2,4]oxadiazolo[4,3-a]quinoxaline-1-one, showed no effect of PDE5A inhibition on beta-stimulated contractility or PKG-1 activation. This lack of response was not attributable to altered PDE5A gene or protein expression or in vitro PDE5A activity, but rather to an absence of sGC-generated cGMP specifically targeted to PDE5A catabolism and to a loss of PDE5A localization to z-bands. Re-expression of active NOS3 in NOS3-null hearts by adenoviral gene transfer restored PDE5A z-band localization and the antiadrenergic efficacy of PDE5A inhibition. These data support a novel regulatory role of PDE5A in hearts under adrenergic stimulation and highlight specific coupling of PDE5A catabolic regulation with NOS3-derived cGMP attributable to protein subcellular localization and targeted synthetic/catabolic coupling.
authors.affiliation: Division of Cardiology, Department of Medicine, Johns Hopkins Medical Institutions, Baltimore, Md, USA.
authors.forename: Eiki
authors.initials: E
authors.lastname: Takimoto
authors.forename: Hunter C
authors.initials: HC
authors.lastname: Champion
authors.forename: Diego
authors.initials: D
authors.lastname: Belardi
authors.forename: Javid
authors.initials: J
authors.lastname: Moslehi
authors.forename: Marco
authors.initials: M
authors.lastname: Mongillo
authors.forename: Evanthia
authors.initials: E
authors.lastname: Mergia
authors.forename: David C
authors.initials: DC
authors.lastname: Montrose
authors.forename: Takayoshi
authors.initials: T
authors.lastname: Isoda
authors.forename: Kate
authors.initials: K
authors.lastname: Aufiero
authors.forename: Manuela
authors.initials: M
authors.lastname: Zaccolo
authors.forename: Wolfgang R
authors.initials: WR
authors.lastname: Dostmann
authors.forename: Carolyn J
authors.initials: CJ
authors.lastname: Smith
authors.forename: David A
authors.initials: DA
authors.lastname: Kass
mesh_terms: D015106:3',5'-Cyclic-GMP Phosphodiesterases / Q000378:metabolism*; D000256:Adenoviridae / Q000235:genetics; D000318:Adrenergic beta-Agonists / Q000494:pharmacology; D000818:Animals; D002243:Carbolines / Q000494:pharmacology; D006152:Cyclic GMP / Q000378:metabolism*; D017869:Cyclic GMP-Dependent Protein Kinases / Q000502:physiology; D054706:Cyclic Nucleotide Phosphodiesterases, Type 5; D031541:Fluorescence Resonance Energy Transfer; D005822:Genetic Vectors / Q000235:genetics; D006162:Guanylate Cyclase; D007545:Isoproterenol / Q000494:pharmacology; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D009200:Myocardial Contraction / Q000187:drug effects / Q000502:physiology*; D019331:NG-Nitroarginine Methyl Ester / Q000494:pharmacology; D009569:Nitric Oxide / Q000096:biosynthesis; D019001:Nitric Oxide Synthase / Q000037:antagonists & inhibitors / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology; D010879:Piperazines / Q000494:pharmacology; D011687:Purines; D051381:Rats; D017207:Rats, Sprague-Dawley; D011943:Receptors, Adrenergic, beta / Q000502:physiology*; D018160:Receptors, Cytoplasmic and Nuclear / Q000037:antagonists & inhibitors / Q000502:physiology; D011993:Recombinant Fusion Proteins / Q000502:physiology; D015290:Second Messenger Systems / Q000502:physiology*; D000068677:Sildenafil Citrate; D000071756:Soluble Guanylyl Cyclase; D013450:Sulfones; D000068581:Tadalafil
chemical_list: D000318:Adrenergic beta-Agonists; D002243:Carbolines; D010726:Phosphodiesterase Inhibitors; D010879:Piperazines; D011687:Purines; D011943:Receptors, Adrenergic, beta; D018160:Receptors, Cytoplasmic and Nuclear; D011993:Recombinant Fusion Proteins; D013450:Sulfones; D009569:Nitric Oxide; D000068581:Tadalafil; D000068677:Sildenafil Citrate; D019001:Nitric Oxide Synthase; D052247:Nitric Oxide Synthase Type II; D052250:Nitric Oxide Synthase Type III; C496315:Nos3 protein, mouse; C496316:Nos3 protein, rat; D017869:Cyclic GMP-Dependent Protein Kinases; D015106:3',5'-Cyclic-GMP Phosphodiesterases; D054706:Cyclic Nucleotide Phosphodiesterases, Type 5; C517382:Pde5a protein, mouse; C517384:Pde5a protein, rat; D006162:Guanylate Cyclase; D000071756:Soluble Guanylyl Cyclase; D006152:Cyclic GMP; D007545:Isoproterenol; D019331:NG-Nitroarginine Methyl Ester