Reciprocal Phosphorylation and Regulation of Endothelial Nitric-oxide Synthase in Response to Bradykinin Stimulation

335Citations
Citations of this article
87Readers
Mendeley users who have this article in their library.

This article is free to access.

Abstract

Endothelial nitric-oxide synthase (eNOS) is phosphorylated at Ser-1179 (bovine sequence) by Akt after growth factor or shear stress stimulation of endothelial cells, resulting in increased eNOS activity. Purified eNOS is also phosphorylated at Thr-497 by purified AMP-activated protein kinase, resulting in decreased eNOS activity. We investigated whether bradykinin (BK) stimulation of bovine aortic endothelial cells (BAECs) regulates eNOS through Akt activation and Ser-1179 or Thr-497 phosphorylation. Akt is transiently activated in BK-stimulated BAECs. Activation is blocked completely by wortmannin and LY294002, inhibitors of phosphatidylinositol 3-kinase, suggesting that Akt activation occurs downstream from phosphatidylinositol 3-kinase. BK stimulates a transient phosphorylation of eNOS at Ser-1179 that is correlated temporally with a transient dephosphorylation of eNOS at Thr-497. Phosphorylation at Ser-1179, but not dephosphorylation at Thr-497, is blocked by wortmannin and LY294002. BK also stimulates a transient nitric oxide (NO) release from BAECs with a time-course similar to Ser-1179 phosphorylation and Thr-497 dephosphorylation. NO release is not altered by wortmannin. BK-stimulated dephosphorylation of Thr-497 and NO release are blocked by the calcineurin inhibitor, cyclosporin A. These data suggest that BK activation of eNOS in BAECs primarily involves deinhibition of the enzyme through calcineurin-mediated dephosphorylation at Thr-497.

Cite

CITATION STYLE

APA

Harris, M. B., Ju, H., Venema, V. J., Liang, H., Zou, R., Michell, B. J., … Venema, R. C. (2001). Reciprocal Phosphorylation and Regulation of Endothelial Nitric-oxide Synthase in Response to Bradykinin Stimulation. Journal of Biological Chemistry, 276(19), 16587–16591. https://doi.org/10.1074/jbc.M100229200

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free