In rat
hepatocytes, atrial natriuretic peptide (ANP) elevates cGMP through activation of particulate guanylyl cyclase and attenuates Ca
2+ signals by stimulating net
plasma membrane Ca
2+ efflux. We show here that ANP-stimulated
hepatocyte Ca
2+ efflux is mediated by protein kinase G (PKG) isotype I. Furthermore, we show that ANP recruits endogenous PKGI
![greek small letter alpha greek small letter alpha](http://www.sciencedirect.com/scidirimg/entities/204e.gif)
, but not PKGIβ, to the
plasma membrane. These effects are mimicked by 8-bromo-cGMP, but not by the soluble guanylyl cyclase activators, sodium nitroprusside and YC-1. We propose that ANP, through localized cGMP elevation, promotes
plasma membrane recruitment of PKGI
![greek small letter alpha greek small letter alpha](http://www.sciencedirect.com/scidirimg/entities/204e.gif)
, which, in turn, stimulates Ca
2+ efflux.