![]() |
|
|
| |||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
Department of Pharmacology and Toxicology, Queen's University, Kingston, Ontario, Canada
Sustained activation of adenylyl cyclase in vascular smooth muscle cells (VSMCs) results in the activation of a series of complex regulatory systems designed to desensitize these cells to further cAMP-mediated events. Although an increase in phosphodiesterase (PDE) 4-mediated hydrolysis of cAMP forms an integral part of this desensitization program in both "contractile/quiescent" and "synthetic/activated" VSMCs, distinct PDE4D gene variants coordinate these events in these phenotypically distinct cells. Using a combination of pharmacological, biochemical, and molecular biological approaches, and both in vivo and in vitro systems, we have identified the molecular basis underlying this VSMC phenotype-selective expression of PDE4D in response to cAMP-elevating agents in these cells. Thus, whereas the protein kinase A/cAMP response element-binding protein/cAMP response element signaling cascade regulates PDE4D expression in each VSMC phenotype, elevated levels of histone acetylation of the intronic promoter regulating PDE4D1 and PDE4D2 expression allows selective cAMP-mediated induction of expression of these PDE4D variants in synthetic/activated VSMCs. In contrast, the newly described EPAC1/Rap1A cAMP-dependent signaling cascade plays no role in regulating PDE4D expression in either VSMC phenotype. Our data are presented in the context of PDE4-mediated desensitization to cAMP-elevating agents in VSMCs and with the recognition that cAMP-elevating agents are being considered as adjunctive pharmacotherapy in percutaneous coronary interventions, including stenting.
Address correspondence to: Dr. Donald H. Maurice, Department of Pharmacology and Toxicology, Queen's University, Kingston, Ontario, Canada, K7L 3N6. E-mail: mauriced{at}post.queensu.ca
This article has been cited by other articles:
![]() |
S. J. Netherton, J. A. Sutton, L. S. Wilson, R. L. Carter, and D. H. Maurice Both Protein Kinase A and Exchange Protein Activated by cAMP Coordinate Adhesion of Human Vascular Endothelial Cells Circ. Res., October 12, 2007; 101(8): 768 - 776. [Abstract] [Full Text] [PDF] |
||||
![]() |
G. Levallet, J. Levallet, H. Bouraima-Lelong, and P.-J. Bonnamy Expression of the cAMP-Phosphodiesterase PDE4D Isoforms and Age-Related Changes in Follicle-Stimulating Hormone-Stimulated PDE4 Activities in Immature Rat Sertoli Cells Biol Reprod, May 1, 2007; 76(5): 794 - 803. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. D. Houslay, G. S. Baillie, and D. H. Maurice cAMP-Specific Phosphodiesterase-4 Enzymes in the Cardiovascular System: A Molecular Toolbox for Generating Compartmentalized cAMP Signaling Circ. Res., April 13, 2007; 100(7): 950 - 966. [Abstract] [Full Text] [PDF] |
||||
![]() |
H. Liu, J. R. Tang, Y. H. Choi, M. Napolitano, S. Hockman, M. Taira, E. Degerman, and V. C. Manganiello Importance of cAMP-response Element-binding Protein in Regulation of Expression of the Murine Cyclic Nucleotide Phosphodiesterase 3B (Pde3b) Gene in Differentiating 3T3-L1 Preadipocytes J. Biol. Chem., July 28, 2006; 281(30): 21096 - 21113. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. D. Houslay The Long and Short of Vascular Smooth Muscle Phosphodiesterase-4 As a Putative Therapeutic Target Mol. Pharmacol., September 1, 2005; 68(3): 563 - 567. [Abstract] [Full Text] [PDF] |
||||