Does adenovirus-mediated gene transfer of PKG increase the sensitivity of cultured vascular smooth muscle cells to the antiproliferative and pro-apoptotic effects of NO/cGMP?
Adenovirus-mediated overexpression of PKG in vascular smooth muscle cells increases their sensitivity to the antiproliferative and pro-apoptotic effects of NO and cGMP.
Studies in vitro have underestimated the importance of cGMP-dependent protein kinase (PKG) in the modulation of vascular smooth muscle cell (SMC) proliferation and apoptosis in vivo. This is attributable, in part, to a rapid decline in PKG levels as vascular SMC are passaged in culture. We used a recombinant adenovirus encoding PKG (Ad.PKG) to augment kinase activity in cultured rat pulmonary artery SMC (RPaSMC). Incubation of Ad.PKG-infected RPaSMC (multiplicity of infection = 200) with 8-Br-cGMP decreased serum-stimulated DNA synthesis by 85% and cell proliferation at day 5 by 74%. The effect of 8-Br-cGMP on DNA synthesis in Ad.PKG-infected RPaSMC was blocked by KT5823 (PKG inhibitor), but not by KT5720 (cAMP-dependent protein kinase inhibitor). A nitric oxide (NO) donor compound,S-nitrosoglutathione, at concentrations as low as 100 nm, inhibited DNA synthesis in Ad.PKG-infected RPaSMC, but not in uninfected cells or in cells infected with a control adenovirus. In addition, 8-Br-cGMP and S-nitrosoglutathione induced apoptosis in serum-deprived RPaSMC infected with Ad.PKG, but not in uninfected cells or in cells infected with a control adenovirus. These results demonstrate that modulation of PKG levels in vascular SMC can alter the sensitivity of these cells to NO and cGMP. Moreover, these observations suggest an important role for PKG in the regulation of vascular SMC proliferation and apoptosis by NO and cGMP. Studies in vitro have underestimated the importance of cGMP-dependent protein kinase (PKG) in the modulation of vascular smooth muscle cell (SMC) proliferation and apoptosis in vivo. This is attributable, in part, to a rapid decline in PKG levels as vascular SMC are passaged in culture. We used a recombinant adenovirus encoding PKG (Ad.PKG) to augment kinase activity in cultured rat pulmonary artery SMC (RPaSMC). Incubation of Ad.PKG-infected RPaSMC (multiplicity of infection = 200) with 8-Br-cGMP decreased serum-stimulated DNA synthesis by 85% and cell proliferation at day 5 by 74%. The effect of 8-Br-cGMP on DNA synthesis in Ad.PKG-infected RPaSMC was blocked by KT5823 (PKG inhibitor), but not by KT5720 (cAMP-dependent protein kinase inhibitor). A nitric oxide (NO) donor compound,S-nitrosoglutathione, at concentrations as low as 100 nm, inhibited DNA synthesis in Ad.PKG-infected RPaSMC, but not in uninfected cells or in cells infected with a control adenovirus. In addition, 8-Br-cGMP and S-nitrosoglutathione induced apoptosis in serum-deprived RPaSMC infected with Ad.PKG, but not in uninfected cells or in cells infected with a control adenovirus. These results demonstrate that modulation of PKG levels in vascular SMC can alter the sensitivity of these cells to NO and cGMP. Moreover, these observations suggest an important role for PKG in the regulation of vascular SMC proliferation and apoptosis by NO and cGMP. nitric oxide smooth muscle cell(s) cGMP-dependent protein kinase cAMP-dependent protein kinase rat aortic smooth muscle cell(s) rat pulmonary artery smooth muscle cell(s) S-nitrosoglutathione plaque-forming unit(s) multiplicity(ies) of infection phosphate-buffered saline adenosine cyclic 3′:5′-phosphorothioate. The endothelium plays a pivotal role in the regulation of vascular tone, the prevention of thrombosis, and the modulation of adhesive interactions between inflammatory cells and the vessel wall. The endothelium modulates the functions of the subjacent vascular smooth muscle, in part, by producing active effector molecules, including angiotensin II, heparinoids, and nitric oxide (NO)1 (1Gibbons G.H. Am. J. Cardiol. 1997; 79: 3-8Abstract Full Text PDF PubMed Scopus (141) Google Scholar, 2Dzau V.J. Gibbons G.H. Hypertension. 1991; 18: III115-III121Crossref PubMed Google Scholar). Endothelial dysfunction is a shared process in the pathogenesis of vascular disorders, including atherosclerosis, neointima formation after angioplasty, and vascular remodeling associated with pulmonary or systemic hypertension (3Ross R. Nature. 1993; 362: 801-809Crossref PubMed Scopus (10004) Google Scholar). This dysfunction is associated with an alteration of the balance between cell growth and apoptosis and with dysregulation of cell-cell as well as cell-matrix interactions (1Gibbons G.H. Am. J. Cardiol. 1997; 79: 3-8Abstract Full Text PDF PubMed Scopus (141) Google Scholar). In addition to its role as an endothelium-derived relaxing factor (4Moncada S. Palmer R.M. Higgs E.A. Pharmacol. Rev. 1991; 43: 109-142PubMed Google Scholar), NO regulates platelet adhesion and aggregation (5Radomski M.W. Palmer R.M. Moncada S. Lancet. 1987; 2: 1057-1058Abstract PubMed Scopus (1234) Google Scholar, 6Radomski M.W. Palmer R.M. Moncada S. Proc. Natl. Acad. Sci. U. S. A. 1990; 87: 5193-5197Crossref PubMed Scopus (1132) Google Scholar), leukocyte recruitment and activation (7Kubes P. Suzuki M. Granger D.N. Proc. Natl. Acad. Aci. U. S. A. 1991; 88: 4651-4655Crossref PubMed Scopus (2822) Google Scholar), and cytokine-induced endothelial cell activation (8Decatarina R. Libby P. Peng H.-B. Thannickai V.J. Rajavashisth T.B. Gimbrone M.A. Shin W.S. Liao J.K. J. Clin. Invest. 1995; 96: 60-68Crossref PubMed Scopus (1586) Google Scholar) as well as vascular smooth muscle cell (SMC) apoptosis (9Pollman M.J. Yamada T. Horiuchi M. Gibbons G.H. Circ. Res. 1996; 79: 748-756Crossref PubMed Scopus (314) Google Scholar, 10Nishio E. Fukushima K. Shiozaki M. Watanabe Y. Biochem. Biophys. Res. Commun. 1996; 221: 163-168Crossref PubMed Scopus (93) Google Scholar, 11Fukuo K. Hata S. Suhara T. Nakahashi T. Shinto Y. Tsujimoto Y. Morimoto S. Ogihara T. Hypertension (Dallas). 1996; 27: 823-826Crossref PubMed Google Scholar), proliferation (12Garg U.C. Hassid A. J. Clin. Invest. 1989; 83: 1774-1777Crossref PubMed Scopus (1997) Google Scholar, 13Kariya K. Kawahara Y. Araki S. Fukuzaki H. Takai Y. Atherosclerosis. 1989; 80: 143-147Abstract Full Text PDF PubMed Scopus (131) Google Scholar, 14Nakaki T. Nakayama M. Kato R. Eur. J. Pharmacol. 1990; 189: 347-353Crossref PubMed Scopus (241) Google Scholar), and migration (15Dubey R.K. Jackson E.K. Luscher T.F. J. Clin. Invest. 1995; 96: 141-149Crossref PubMed Scopus (301) Google Scholar, 16Sarkar R. Meinberg E.G. Stanley J.C. Gordon D. Webb R.C. Circ. Res. 1996; 78: 225-230Crossref PubMed Scopus (357) Google Scholar). NO acts, in part, by stimulating soluble guanylate cyclase to produce the intracellular second messenger cGMP (17Hobbs A.J. Ignarro L.J. Zapol W.M. Bloch K.D. Nitric Oxide and the Lung. Marcel Dekker, Inc., New York1997: 1-57Google Scholar). cGMP activates cGMP-dependent protein kinase (PKG), leading to many of the effects of NO (18Lincoln T.M. Cornwell T.L. FASEB J. 1993; 7: 328-338Crossref PubMed Scopus (543) Google Scholar). The two isoforms of PKG detected in vascular smooth muscle (Iα and Iβ) share substrate-binding/catalytic domains, but differ in cGMP affinity (19Sekhar K.R. Hatchett R.J. Shabb E. Pharmacol. Google Scholar, P. A. S. P. J. 1997; Full Text Full Text PDF PubMed Scopus Google Scholar). The effects of NO on vascular SMC proliferation have that NO proliferation of vascular SMC with (12Garg U.C. Hassid A. J. Clin. Invest. 1989; 83: 1774-1777Crossref PubMed Scopus (1997) Google Scholar, 13Kariya K. Kawahara Y. Araki S. Fukuzaki H. Takai Y. Atherosclerosis. 1989; 80: 143-147Abstract Full Text PDF PubMed Scopus (131) Google Scholar, 14Nakaki T. Nakayama M. Kato R. Eur. J. Pharmacol. 1990; 189: 347-353Crossref PubMed Scopus (241) Google 1997; PubMed Scopus Google Scholar, Am. J. 1995; PubMed Google Scholar, J. Pharmacol. 1995; PubMed Scopus Google Scholar, T.L. E. T.M. Am. J. PubMed Google Scholar, R. Gordon D. Stanley J.C. Webb R.C. Am. J. 1997; PubMed Google Scholar, Biochem. J. PubMed Scopus Google Scholar), the for effect are In the effect of NO on SMC was a cGMP-dependent (12Garg U.C. Hassid A. J. Clin. Invest. 1989; 83: 1774-1777Crossref PubMed Scopus (1997) Google Scholar, 13Kariya K. Kawahara Y. Araki S. Fukuzaki H. Takai Y. Atherosclerosis. 1989; 80: 143-147Abstract Full Text PDF PubMed Scopus (131) Google Scholar, 14Nakaki T. Nakayama M. Kato R. Eur. J. Pharmacol. 1990; 189: 347-353Crossref PubMed Scopus (241) Google Scholar, 1997; PubMed Scopus Google Scholar, Am. J. 1995; PubMed Google Scholar, J. Pharmacol. 1995; PubMed Scopus Google Scholar). 1997; PubMed Scopus Google Scholar) that decreased DNA synthesis and proliferation of growth vascular The effects of cGMP on DNA synthesis and cell proliferation inhibited by the PKG KT5823 1997; PubMed Scopus Google Scholar). These results differ of Cornwell T.L. E. T.M. Am. J. PubMed Google Scholar), that NO and cGMP inhibited proliferation of cultured rat aortic SMC a by cAMP-dependent protein kinase and not by the role of NO in the of the cell (9Pollman M.J. Yamada T. Horiuchi M. Gibbons G.H. Circ. Res. 1996; 79: 748-756Crossref PubMed Scopus (314) Google Scholar, 10Nishio E. Fukushima K. Shiozaki M. Watanabe Y. Biochem. Biophys. Res. Commun. 1996; 221: 163-168Crossref PubMed Scopus (93) Google Scholar, 11Fukuo K. Hata S. Suhara T. Nakahashi T. Shinto Y. Tsujimoto Y. Morimoto S. Ogihara T. Hypertension (Dallas). 1996; 27: 823-826Crossref PubMed Google Scholar, J. K. Biophys. 1997; PubMed Scopus Google Scholar, S. U. J. Circ. Res. 1997; PubMed Scopus Google Scholar, S. J. M. J. 1997; PubMed Scopus Google Scholar, E. A. 1997; Full Text PDF PubMed Scopus (141) Google Scholar, J. 1997; PubMed Scopus Google Scholar). NO to a of cell of or stimulating apoptosis on the cell and the of NO that concentrations of NO donor apoptosis in vascular SMC (9Pollman M.J. Yamada T. Horiuchi M. Gibbons G.H. Circ. Res. 1996; 79: 748-756Crossref PubMed Scopus (314) Google Scholar, 10Nishio E. Fukushima K. Shiozaki M. Watanabe Y. Biochem. Biophys. Res. Commun. 1996; 221: 163-168Crossref PubMed Scopus (93) Google Scholar, 11Fukuo K. Hata S. Suhara T. Nakahashi T. Shinto Y. Tsujimoto Y. Morimoto S. Ogihara T. Hypertension (Dallas). 1996; 27: 823-826Crossref PubMed Google Scholar, J. K. Biophys. 1997; PubMed Scopus Google Scholar). to the role of cGMP in the activation of SMC results (9Pollman M.J. Yamada T. Horiuchi M. Gibbons G.H. Circ. Res. 1996; 79: 748-756Crossref PubMed Scopus (314) Google Scholar, 10Nishio E. Fukushima K. Shiozaki M. Watanabe Y. Biochem. Biophys. Res. Commun. 1996; 221: 163-168Crossref PubMed Scopus (93) Google Scholar, 11Fukuo K. Hata S. Suhara T. Nakahashi T. Shinto Y. Tsujimoto Y. Morimoto S. Ogihara T. Hypertension (Dallas). 1996; 27: 823-826Crossref PubMed Google Scholar, J. K. Biophys. 1997; PubMed Scopus Google Scholar). PKG as vascular SMC are passaged in T.M. P. Cornwell T.L. Hypertension (Dallas). PubMed Scopus Google Scholar, T.L. T.M. J. Res. PubMed Scopus Google Scholar), the of PKG to the modulation of vascular SMC proliferation and apoptosis by NO donor and cGMP is to the role of PKG in the regulation of the balance between SMC proliferation and SMC used to PKG activity in cultured rat pulmonary artery SMC (RPaSMC). We that of PKG activity in RPaSMC, inhibited proliferation induced by and apoptosis associated with Moreover, PKG the sensitivity of vascular SMC to the and effects of NO and cGMP. These by the for Studies at the was and the protein kinase KT5823 and A was to a PKG rat to and shared by and and J. T. A Scholar, J. 1989; Full Text PDF PubMed Google Scholar, M. D. U. T. 1989; PubMed Scopus Google Scholar). The was and its was a a was of the rat a to of the for M. D. U. T. 1989; PubMed Scopus Google Scholar). This was used to the in the of a second to of the The two to produce a the The was The of was the and of the by of the as a and the a encoding the a and 1996; PubMed Scopus Google Scholar). The was cells with by PubMed Scopus Google Scholar). the for detected The recombinant adenovirus was and in cells as and Inc., Scholar). recombinant used as the of the protein R.J. U. T. J.K. M.J. A. Proc. Natl. Acad. Sci. U. S. A. PubMed Scopus Google Scholar), and a of by D. for J. 1996; Full Text Full Text PDF PubMed Scopus Google Scholar). The of used for these was plaque-forming and with of and of with was by the of effect after infection of a of cells with and by the to a of the of RPaSMC of and pulmonary of as Am. Rev. 1989; Scopus Google Scholar). RPaSMC in with and used between and RPaSMC at a of 5 in and infected with of infection to for of the cells for and in and 5 and The cell was and at for at of cell by and to blocked at for in phosphate-buffered and for at with an in at a of the with a in an and to RPaSMC on and infected with = The was after and cells in with and cells in for at in with in in and with in in cells with the in at and with Inc., in to a of after a of the was uninfected cells and cells infected with as well as by the The of cells the at and after infection was the activity of the PKG activity was in RPaSMC infected with 1991; PubMed Scopus Google Scholar). 5 infected with = cells and in of at for at of the protein a protein the of cell in a a Inc., The H. J. Full Text PDF PubMed Google Scholar), 100 and in the or of cGMP at for and by and in in and to the was by PKG activity is as of of cell RPaSMC in and infected with or = the was and cells in for to a The was with or with or KT5720 or of these the and in and was to a of cells the and DNA was to Inc., a cell and and DNA was by used for and was in for RPaSMC in and infected with or = The was after and cells in with for in or in the or of cells with and with a at and was by and the of cells in the was The was used to as a of apoptosis the cell RPaSMC on and infected with or = The was after and cells in The was and with or KT5823 or of these cells in in in and with by was by the of or of by an as to the The of was as the of to the of DNA RPaSMC cultured in infected with or = and low after the cells with and in in the or of 8-Br-cGMP for cells the with and with cells in the by in and for at in 100 5 and K. The DNA was with of in and with and in the of and with for at DNA was by the at and DNA and and by on and to for at was a of are as the was by of by for the of proliferation of vascular SMC for of cell was and the of the as a of of A of was augment PKG activity in vascular SMC in used a recombinant adenovirus encoding the A was at the to levels of PKG protein in cultured SMC RPaSMC infected with concentrations of = and and the of the recombinant PKG protein was by after of PKG was in cell RPaSMC infected at = and in a The recombinant protein was as as at and for after infection not that the not with the activity of the PKG activity was in cell RPaSMC infected with = in PKG at = 100 in a in PKG activity was in cell RPaSMC infected at at = in a PKG activity of of is to the activity in of T.L. T.M. J. 1989; Full Text PDF PubMed Google Scholar) as well as in rat pulmonary not of SMC with a control adenovirus not PKG the to the of vascular SMC in RPaSMC with at and the of cells PKG was by an and a was detected in and of RPaSMC infected with at 100 and but not in RPaSMC infected with was of effect in vascular SMC infected with at the effect of PKG on DNA synthesis in vascular RPaSMC infected with = and to DNA with with cells in with in an in DNA synthesis in RPaSMC, as by not of PKG decreased in a The effect was in RPaSMC infected at = and of RPaSMC with not PKG to a cGMP the effect of of RPaSMC at = 100 decreased DNA synthesis in the but not in the of The in was in RPaSMC with = in uninfected the effect of infection = on the sensitivity of RPaSMC to the effects of was in cells in the of and in of Ad.PKG-infected cells with as as inhibited DNA synthesis as with infected cells with the sensitivity of RPaSMC to the effects of of Ad.PKG-infected cells with as as NO donor decreased as with Ad.PKG-infected cells In concentrations of 8-Br-cGMP and to and not alter DNA synthesis in uninfected RPaSMC or in RPaSMC infected with a control recombinant adenovirus = These results suggest that the effects of infection on DNA synthesis Moreover, PKG the sensitivity of vascular SMC to the effects of NO and the effect of on DNA synthesis in Ad.PKG-infected vascular RPaSMC in in the of adenovirus or in the of or = for of in with the was with In in the the was with 8-Br-cGMP with or In in with or KT5823 was to the the was in well and was was after are as the = 8-Br-cGMP and decreased DNA synthesis in Ad.PKG-infected RPaSMC, but not in uninfected or The effect of 8-Br-cGMP or was by uninfected Ad.PKG-infected cells not with 8-Br-cGMP or Ad.PKG-infected cells with 8-Br-cGMP or that the effect of NO was 1997; PubMed Scopus Google Scholar). the of cyclic protein in vascular used protein kinase that are for PKG and KT5823 and Incubation of uninfected vascular SMC with KT5823 induced a in serum-stimulated not KT5720 not alter DNA synthesis at concentrations between and with KT5823 the effects of 8-Br-cGMP and on Ad.PKG-infected RPaSMC In uninfected KT5720 blocked the effect of a KT5720 not the activity of 8-Br-cGMP in Ad.PKG-infected cells these results suggest that the effects of on Ad.PKG-infected cells are of DNA synthesis was associated with a in the of cell uninfected RPaSMC and RPaSMC infected with or that in the of with or 8-Br-cGMP and RPaSMC in for at the of cells not differ the was and with with or for 5 and the of proliferation was by the of the of cell as a of in The of proliferation not differ for uninfected RPaSMC and RPaSMC infected with or Incubation of uninfected or RPaSMC with 8-Br-cGMP not alter the of cell 8-Br-cGMP inhibited the proliferation of RPaSMC infected with that the effect of PKG not cell was by and was to in Moreover, the of cells in the for 5 after was to and not differ These demonstrate that PKG the sensitivity of vascular SMC to the effects of cGMP. the that PKG activation apoptosis of vascular RPaSMC infected with or and uninfected cells in in the or of and the of uninfected and Ad.PKG-infected RPaSMC, with 8-Br-cGMP for The of uninfected RPaSMC with 8-Br-cGMP was In the of Ad.PKG-infected cells with 8-Br-cGMP was not with many cells and that PKG activation induced cell DNA was RPaSMC for of DNA by Incubation of Ad.PKG-infected RPaSMC with 8-Br-cGMP for in a of DNA of apoptosis In of DNA by not DNA in uninfected RPaSMC with 8-Br-cGMP or in cells in the or of 8-Br-cGMP not the of on vascular SMC the of cells with was by an as to the with an of Ad.PKG-infected cells in the of 8-Br-cGMP uninfected the of not differ between and RPaSMC in the of that adenovirus infection was associated with a in cells apoptosis Incubation with 8-Br-cGMP for the with Ad.PKG-infected RPaSMC but not apoptosis in uninfected or that the effect of cGMP was by RPaSMC infected with low in the of and The PKG blocked the effect of cGMP in RPaSMC with Ad.PKG, but not alter the of in uninfected cells or cells infected with infection with the sensitivity of vascular SMC to the effect of uninfected RPaSMC and or RPaSMC in the of and the of was In uninfected the of not after with In after with for of the Ad.PKG-infected RPaSMC of apoptosis of RPaSMC in inhibited apoptosis in not that apoptosis not to the effect of PKG that in Ad.PKG-infected cells with or these results suggest that PKG activation can apoptosis in serum-deprived vascular SMC and that PKG the sensitivity of vascular SMC to the effects of NO and cGMP. of SMC proliferation and apoptosis is a of the vascular remodeling associated with endothelial dysfunction and (1Gibbons G.H. Am. J. Cardiol. 1997; 79: 3-8Abstract Full Text PDF PubMed Scopus (141) Google Scholar). is well that NO or vascular remodeling Am. J. 1995; PubMed Google Scholar, M. M. PubMed Scopus (131) Google Scholar, H. Ignarro L.J. Biochem. Biophys. Res. Commun. 1993; PubMed Scopus Google Scholar, S. D. P. R. D. PubMed Scopus Google Scholar, J. J. Clin. Invest. 1995; 96: PubMed Scopus Google Scholar), is effect is by a of NO on vascular SMC or NO by the of growth cell as and in NO regulates many functions of vascular including SMC proliferation (12Garg U.C. Hassid A. J. Clin. Invest. 1989; 83: 1774-1777Crossref PubMed Scopus (1997) Google Scholar, 13Kariya K. Kawahara Y. Araki S. Fukuzaki H. Takai Y. Atherosclerosis. 1989; 80: 143-147Abstract Full Text PDF PubMed Scopus (131) Google Scholar, 14Nakaki T. Nakayama M. Kato R. Eur. J. Pharmacol. 1990; 189: 347-353Crossref PubMed Scopus (241) Google Scholar, 1997; PubMed Scopus Google Scholar, Am. J. 1995; PubMed Google Scholar, J. Pharmacol. 1995; PubMed Scopus Google Scholar, T.L. E. T.M. Am. J. PubMed Google Scholar, R. Gordon D. Stanley J.C. Webb R.C. Am. J. 1997; PubMed Google Scholar, Biochem. J. PubMed Scopus Google Scholar), migration (15Dubey R.K. Jackson E.K. Luscher T.F. J. Clin. Invest. 1995; 96: 141-149Crossref PubMed Scopus (301) Google Scholar, 16Sarkar R. Meinberg E.G. Stanley J.C. Gordon D. Webb R.C. Circ. Res. 1996; 78: 225-230Crossref PubMed Scopus (357) Google Scholar), apoptosis (9Pollman M.J. Yamada T. Horiuchi M. Gibbons G.H. Circ. Res. 1996; 79: 748-756Crossref PubMed Scopus (314) Google Scholar, 10Nishio E. Fukushima K. Shiozaki M. Watanabe Y. Biochem. Biophys. Res. Commun. 1996; 221: 163-168Crossref PubMed Scopus (93) Google Scholar, 11Fukuo K. Hata S. Suhara T. Nakahashi T. Shinto Y. Tsujimoto Y. Morimoto S. Ogihara T. Hypertension (Dallas). 1996; 27: 823-826Crossref PubMed Google J. K. Biophys. 1997; PubMed Scopus Google Scholar), and formation Gordon D. Circ. Res. 1995; PubMed Google Scholar). the concentrations of NO to these effects are to in (12Garg U.C. Hassid A. J. Clin. Invest. 1989; 83: 1774-1777Crossref PubMed Scopus (1997) Google Scholar, 13Kariya K. Kawahara Y. Araki S. Fukuzaki H. Takai Y. Atherosclerosis. 1989; 80: 143-147Abstract Full Text PDF PubMed Scopus (131) Google Scholar, 14Nakaki T. Nakayama M. Kato R. Eur. J. Pharmacol. 1990; 189: 347-353Crossref PubMed Scopus (241) Google Scholar, 1997; PubMed Scopus Google Am. J. 1995; PubMed Google Scholar). Moreover, in the effects of NO on vascular SMC functions to and R. Gordon D. Stanley J.C. Webb R.C. Am. J. 1997; PubMed Google Scholar, T.M. P. Cornwell T.L. Hypertension (Dallas). PubMed Scopus Google Scholar, T.L. T.M. J. Res. PubMed Scopus Google Scholar). Cornwell and T.M. P. Cornwell T.L. Hypertension (Dallas). PubMed Scopus Google Scholar, T.L. T.M. J. Res. PubMed Scopus Google Scholar) that levels of PKG decline as vascular SMC are passaged in culture. is that of the effects of NO on vascular SMC in have underestimated the of cGMP and PKG in vivo. the role of PKG in vascular SMC proliferation and used to PKG activity in cultured In a S. A. U. A. Proc. Natl. Acad. Sci. U. S. A. PubMed Scopus Google Scholar) used a to the role of in the modulation of by We that of PKG activity in RPaSMC decreased serum-stimulated DNA synthesis and cell The effect of PKG in RPaSMC was blocked by the but not by the These are by of 1997; PubMed Scopus Google Scholar), that of PKG in vascular smooth muscle cells the effects of NO and cGMP. Moreover, in SMC cGMP proliferation PKG results differ the observations of Cornwell T.L. T.M. J. Res. 1997; PubMed Scopus Google Scholar), that PKG not a role in vascular SMC These with the or the active PKG is shared by growth proliferation not differ in with and with the PKG In addition, the that infection of with recombinant PKG kinase the effect of PKG on cell proliferation was not are for the between observations and of used RPaSMC and in PKG sensitivity between SMC This is that of PKG activity in decreased serum-stimulated DNA synthesis and apoptosis associated with not A second for the results to in the used in the two growth A for these results is that of SMC cell and for cell in and of the to to the effects of PKG In PKG to the of PKG activation on SMC functions in cells In of PKG activity induced apoptosis in serum-deprived These are with of (9Pollman M.J. Yamada T. Horiuchi M. Gibbons G.H. Circ. Res. 1996; 79: 748-756Crossref PubMed Scopus (314) Google Scholar), that PKG an important role in vascular SMC apoptosis induced by concentrations of In that the effect of NO on vascular SMC was E. Fukushima K. Shiozaki M. Watanabe Y. Biochem. Biophys. Res. Commun. 1996; 221: 163-168Crossref PubMed Scopus (93) Google Scholar, 11Fukuo K. Hata S. Suhara T. Nakahashi T. Shinto Y. Tsujimoto Y. Morimoto S. Ogihara T. Hypertension (Dallas). 1996; 27: 823-826Crossref PubMed Google Scholar, J. K. Biophys. 1997; PubMed Scopus Google Scholar). E. Fukushima K. Shiozaki M. Watanabe Y. Biochem. Biophys. Res. Commun. 1996; 221: 163-168Crossref PubMed Scopus (93) Google Scholar) that NO donor but not vascular SMC apoptosis and that of the J. K. Biophys. 1997; PubMed Scopus Google Scholar) that concentrations of induced vascular SMC but cGMP that NO induced apoptosis by intracellular levels of and of the observations suggest that the in the of cGMP on apoptosis of cultured vascular SMC in these to in PKG Moreover, results suggest in cells kinase is an important of vascular cell apoptosis induced by NO and cGMP. A of is that PKG the sensitivity of RPaSMC to the and effects of activation of the PKG with concentrations of decreased vascular SMC and low concentrations of induced apoptosis of vascular The of NO by these concentrations of are to by endothelial cells A.J. S. T. Circ. Res. 1995; PubMed Scopus Google Scholar, K. H. M. H. E. Rev. Sci. Scopus Google Scholar) and to to J. Pharmacol. 1993; Google Scholar). important is that levels of PKG in RPaSMC are to in vascular SMC T.L. T.M. J. 1989; Full Text PDF PubMed Google Scholar) and in rat pulmonary or not The role of endothelial NO in vascular SMC proliferation and apoptosis the concentrations of NO to these functions in cultured cells are in vivo. observations in Ad.PKG-infected RPaSMC suggest that levels of as by vascular endothelial can proliferation and apoptosis in vascular smooth muscle cells PKG as in This is by the that vascular smooth muscle cells in levels of the (18Lincoln T.M. Cornwell T.L. FASEB J. 1993; 7: 328-338Crossref PubMed Scopus (543) Google Scholar), is to cGMP the used in (19Sekhar K.R. Hatchett R.J. Shabb E. Pharmacol. Google Scholar, P. A. S. P. J. 1997; Full Text Full Text PDF PubMed Scopus Google Scholar). The observations that the PKG levels in RPaSMC modulates the sensitivity of these cells to the and effects of NO and with the in PKG modulates cell migration Cornwell T.L. T.M. J. Res. 1997; PubMed Scopus Google Scholar) and synthesis T.M. Circ. Res. PubMed Scopus Google Scholar), suggest that in PKG levels can the of NO to important vascular cell in PKG levels have in growth vascular SMC H. Y. M. S. T. K. Hypertension (Dallas). 1996; 27: PubMed Google Scholar), in aortic SMC to that or cGMP Cornwell T.L. S. T.M. J. Clin. Invest. 1997; PubMed Scopus Google Scholar), and in and of Cornwell T.L. S. T.M. J. Clin. Invest. 1997; PubMed Scopus Google Scholar). In of of vascular associated with Cornwell T.M. T.M. J. Res. 1996; Scholar), decreased PKG levels in the smooth muscle cells of the neointima as with of the and Circ. Res. PubMed Scopus Google Scholar) in the rat artery of vascular that cultured cells the neointima are to the effects of NO cells the is that decreased PKG levels to the of cells to the effect of In used to PKG activity in vascular results the importance of PKG in the effects of NO and suggest that in endothelium-derived NO synthesis the proliferation of the subjacent vascular We the role of the in the activation of cell in to These have important for the of to augment the of NO in the of associated with endothelial dysfunction and vascular We M. Zapol for and and and for
Chiche et al. (Tue,) studied this question.