La. Macmillancrow et al., IDENTIFICATION AND POSSIBLE LOCALIZATION OF CGMP-DEPENDENT PROTEIN-KINASE IN BOVINE AORTIC ENDOTHELIAL-CELLS, Biochemical and biophysical research communications, 201(2), 1994, pp. 531-537
Endothelial-derived nitric oxide (NO) is an important intercellular me
ssenger. Although endothelial cells contain both nitric oxide synthase
and soluble guanylate cyclase, the nature of receptor proteins for cG
MP is uncertain. Based on previous work in vascular smooth muscle cell
s which indicates that the cGMP-dependent protein kinase (cGK) is part
ially associated with the cytoskeleton, we determined that cGK was pre
sent in non-cytosolic fractions of endothelial cells. The data reveal
that cGK is found only in Triton-soluble extracts of particulate fract
ions from bovine aortic endothelial cells and provide the first eviden
ce for the existence of cGK in this cell type based on immunoreactivit
y, immunofluorescence microscopy and phosphotransferase activity. The
limited distribution of endothelial cell cGK may explain why this kina
se has not been heretofore identified in endothelial cells. (C) 1994 A
cademic Press, Inc.