title: Cyclic GMP-specific phosphodiesterase 5 regulates growth and apoptosis in pulmonary endothelial cells.
abstract: Sustained increases in intracellular cGMP concentrations ([cGMP]i) inhibit cell growth and induce apoptosis. We now report that a cGMP-specific phosphodiesterase, PDE5, plays a dominant role in regulating [cGMP]i transitions that inhibit cell growth and control susceptibility to apoptosis in pulmonary endothelium. Atrial natriuretic peptide (ANP) activates guanylyl cyclase A/B and induces a rapid [cGMP]i rise 2-5 min after its application, in both pulmonary arterial endothelial cells (PAECs) and pulmonary microvascular endothelial cells (PMVECs). However, increased [cGMP]i in PAECs is transient and decays within 10 min due to cytosolic PDE5 hydrolytic activity. Increased [cGMP]i in PMVECs is sustained for >3 h due to the absence of PDE5. Indeed, at any ANP concentration, the sustained (30 min) [cGMP]i rise is greater in PMVECs than in PAECs, unless PAECs are also treated with the PDE5 inhibitor zaprinast. Using RT-PCR, Western blot analysis, immunoprecipitation, and DEAE chromatography, we resolved the expression and activity of PDE 5A1/A2 only in PAECs. Similarly, PDE5 expression was restricted to extra-alveolar endothelium in vivo. ANP induced growth inhibition and apoptosis in PMVECs, but similar effects were not seen in PAECs unless ANP treatment was combined with zaprinast. ANP blocked the VEGF-induced proliferation and migration in PMVECs. Collectively, these data suggest that PDE5-regulated [cGMP]i controls endothelial cell growth and apoptosis, representing a mechanism of heterogeneity between two endothelial phenotypes.
authors.affiliation: Dept. of Pharmacology, Center for Lung Biology, Univ. of So. Alabama College of Medicine, CSAB 345, 301 N. Univ. Blvd., Mobile, AL 36688, USA. zbing@jaguar1.usouthal.edu
authors.forename: Bing
authors.initials: B
authors.lastname: Zhu
authors.forename: Samuel
authors.initials: S
authors.lastname: Strada
authors.forename: Troy
authors.initials: T
authors.lastname: Stevens
mesh_terms: D015106:3',5'-Cyclic-GMP Phosphodiesterases / Q000037:antagonists & inhibitors; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D009320:Atrial Natriuretic Factor / Q000494:pharmacology; D002465:Cell Movement / Q000187:drug effects; D049109:Cell Proliferation / Q000187:drug effects*; D006152:Cyclic GMP / Q000378:metabolism*; D054706:Cyclic Nucleotide Phosphodiesterases, Type 5; D004730:Endothelium, Vascular / Q000201:enzymology / Q000473:pathology*; D004789:Enzyme Activation / Q000187:drug effects; D006162:Guanylate Cyclase / Q000378:metabolism; D047468:Immunoprecipitation; D010726:Phosphodiesterase Inhibitors / Q000494:pharmacology; D010727:Phosphoric Diester Hydrolases / Q000378:metabolism / Q000494:pharmacology*; D011650:Pulmonary Alveoli / Q000166:cytology / Q000378:metabolism; D011651:Pulmonary Artery / Q000166:cytology / Q000378:metabolism; D011688:Purinones / Q000494:pharmacology; D051381:Rats; D017461:Receptors, Atrial Natriuretic Factor / Q000378:metabolism; D042461:Vascular Endothelial Growth Factor A / Q000494:pharmacology
chemical_list: D010726:Phosphodiesterase Inhibitors; D011688:Purinones; D042461:Vascular Endothelial Growth Factor A; D009320:Atrial Natriuretic Factor; D010727:Phosphoric Diester Hydrolases; D015106:3',5'-Cyclic-GMP Phosphodiesterases; D054706:Cyclic Nucleotide Phosphodiesterases, Type 5; C517384:Pde5a protein, rat; D006162:Guanylate Cyclase; D017461:Receptors, Atrial Natriuretic Factor; C091715:atrial natriuretic factor receptor A; C011145:zaprinast; D006152:Cyclic GMP