Skip to main content

Regulation of intracellular Ca2+ and calcineurin by NO/PKG in proliferation of vascular smooth muscle cells

Buy Article:

$51.00 plus tax (Refund Policy)

Abstract:

Abstract Aim:

To determine whether Ca2+/calcineurin mediated the inhibitory effects of nitric oxide /cGMP-dependent protein kinase (NO/PKG) on the proliferation of vascular smooth muscle cells (VSMC). Methods:

Proliferation and viability of primary VSMC from rat aorta were measured using [3-(4,5-dimethyl thiazol-2-yl)-2, 5-diphenyl tetrazolium bromide] (MTT) assay and acridine orange and ethidium bromide staining, respectively. Cytosolic Ca2+ was determined by Fluo-3/AM. Calcineurin protein and its activity were assayed using immunoblotting and free inorganic phosphate analysis, respectively. Results:

(±)-S-nitroso-N-acetyl-penicillamine (SNAP) and Sp-8-(4-chlorophenylthio)-guanosine-3′,5′-cyclic monophosphorothioate (Sp-8-pCPT-cGMPS) decreased phenylephrine (PE)-induced proliferation of VSMC by 27.3% and 36.6%, respectively, but Rp-8-[(4-chlorophenyl)thio]-guanosine-3′,5′-cyclic monophosphorothioate (Rp-8-pCPTcGMPS) increased PE-induced proliferation of VSMC. SNAP, Sp-8-pCPT-cGMPS, and Rp-8-pCPT-cGMPS did not affect the viability of VSMC. Calcineurin protein was decreased by 63.1% and its activity was decreased by 59.7% in smooth muscle cells (SMC) pretreated with verapamil (Ver) and then stimulated by PE. In SMC pretreated with Ver, the absorbance of cells stimulated by PE decreased by 22.0% and was further inhibited by the additional treatment of SNAP and Sp-8-pCPTcGMPS. In SMC pretreated with cyclosporin A (CsA), the absorbance of cells stimulated by PE decreased by 36.7%, but could not be further altered by the additional treatment of SNAP, Sp-8-pCPT-cGMPS, and Rp-8-pCPT-cGMPS. In addition, Ver inhibited PE-induced intracellular Ca2+ variations, which could be further inhibited by SNAP and Sp-8-pCPT-cGMPS, but not by Rp-8-pCPT-cGMPS. Moreover, the increase in calcineurin activity induced by PE was inhibited by SNAP and Sp-8-pCPT-cGMPS, but was promoted by Rp-8-pCPT-cGMPS. Conclusion:

NO/PKG regulates calcineurin activity via the modulation of intracellular Ca2+ concentration, and thus partially inhibits the proliferation of VSMC without affecting their viability.

Keywords: cGMP-dependent protein kinase; calcineurin; calcium; nitric oxide; vascular smooth muscle

Document Type: Research Article

DOI: http://dx.doi.org/10.1111/j.1745-7254.2005.00049.x

Affiliations: Department of Cardiology, People's Hospital, Peking University, Beijing 100044, China

Publication date: March 1, 2005

bsc/aphs/2005/00000026/00000003/art00010
dcterms_title,dcterms_description,pub_keyword
6
5
20
40
5

Access Key

Free Content
Free content
New Content
New content
Open Access Content
Open access content
Subscribed Content
Subscribed content
Free Trial Content
Free trial content
Cookie Policy
X
Cookie Policy
ingentaconnect website makes use of cookies so as to keep track of data that you have filled in. I am Happy with this Find out more