Angiotensin II increases phosphodiesterase 5A expression in vascular smooth muscle cells: A mechanism by which angiotensin II antagonizes cGMP signaling

• Published in: Journal of molecular and cellular cardiology Vol. 38; no. 1; pp. 175 - 184
• Main Authors: Kim, Dongsoo, Aizawa, Toru, Wei, Heng, Pi, Xinchun, Rybalkin, Sergei D., Berk, Bradford C., Yan, Chen
• Format: Journal Article
• Language: English
• Published: England Elsevier Ltd 01.01.2005
• Subjects: 3',5'-Cyclic-GMP Phosphodiesterases - antagonists & inhibitors; 3',5'-Cyclic-GMP Phosphodiesterases - genetics; 3',5'-Cyclic-GMP Phosphodiesterases - metabolism; Angiotensin II; Angiotensin II - pharmacology; Animals; Cell growth; Cell Proliferation - drug effects; Cells, Cultured; cGMP; Cyclic GMP - metabolism; Cyclic nucleotide phosphodiesterase; Cyclic Nucleotide Phosphodiesterases, Type 5; Extracellular Signal-Regulated MAP Kinases - metabolism; Gene Expression Regulation, Enzymologic - drug effects; Male; Muscle, Smooth, Vascular - cytology; Muscle, Smooth, Vascular - drug effects; Muscle, Smooth, Vascular - enzymology; Muscle, Smooth, Vascular - metabolism; Protein Kinase Inhibitors - pharmacology; Rats; Rats, Sprague-Dawley; RNA, Messenger - genetics; RNA, Messenger - metabolism; Signal Transduction - drug effects; Transcription, Genetic - drug effects; Transcription, Genetic - genetics; Up-Regulation - drug effects; Vascular smooth muscle cell; Vascular smooth muscle cell; cGMP; Cell growth; Angiotensin II; Cyclic nucleotide phosphodiesterase
• ISSN: 0022-2828; 1095-8584
• DOI: 10.1016/j.yjmcc.2004.10.013

Angiotensin II (Ang II) and nitric oxide (NO)/natriuretic peptide (NP) signaling pathways mutually regulate each other. Imbalance of Ang II and NO/NP has been implicated in the pathophysiology of many vascular diseases. cGMP functions as a key mediator in the interaction between Ang II and NO/NP. Cyclic nucleotide phosphodiesterase 5A (PDE5A) is important in modulating cGMP signaling by hydrolyzing cGMP in vascular smooth muscle cells (VSMC). Therefore, we examined whether Ang II negatively modulates intracellular cGMP signaling in VSMC by regulating PDE5A. Ang II rapidly and transiently increased PDE5A mRNA levels in rat aortic VSMC. Upregulation of PDE5A mRNA was associated with a time-dependent increase of both PDE5 protein expression and activity. Increased PDE5A mRNA level was transcription-dependent and mediated by the Ang II type 1 receptor. Ang II-mediated activation of extracellular signal-regulated kinases 1/2 (ERK1/2) was essential for Ang II-induced PDE5A upregulation. Pretreatment of VSMC with Ang II inhibited C-type NP (CNP) stimulated cGMP signaling, such as cGMP dependent protein kinase (PKG)-mediated phosphorylation of vasodilator-stimulated-phosphoprotein (VASP). Ang II-mediated inhibition of PKG was blocked when PDE5 activity was decreased by selective PDE5 inhibitors, suggesting that upregulation of PDE5A expression is an important mechanism for Ang II to attenuate cGMP signaling. PDE5A may also play a critical role in the growth promoting effects of Ang II because inhibition of PDE5A activity significantly decreased Ang II-stimulated VSMC growth. These observations establish a new mechanism by which Ang II antagonizes cGMP signaling and stimulates VSMC growth.