title: 17Beta-estradiol elevates cGMP and, via plasma membrane recruitment of protein kinase GIalpha, stimulates Ca2+ efflux from rat hepatocytes.
abstract: Rapid non-genomic effects of 17beta-estradiol, the principal circulating estrogen, have been observed in a wide variety of cell types. Here we investigate rapid signaling effects of 17beta-estradiol in rat hepatocytes. We show that, above a threshold concentration of 1 nm, 17beta-estradiol, but not 17alpha-estradiol, stimulates particulate guanylyl cyclase to elevate cGMP, which through activation and plasma membrane recruitment of protein kinase G isoform Ialpha, stimulates plasma membrane Ca(2+)-ATPase-mediated Ca(2+) efflux from rat hepatocytes. These effects are extremely rapid in onset and are mimicked by a membrane-impermeant 17beta-estradiol-BSA conjugate, suggesting that 17beta-estradiol acts at the extracellular face of the plasma membrane. We also show that 17beta-estradiol binds specifically to the intact hepatocyte plasma membrane through an interaction that is competed by an excess of atrial natriuretic peptide but also shows many similarities to the pharmacological characteristics of the putative gamma-adrenergic receptor. We, therefore, propose that the observed rapid signaling effects of 17beta-estradiol are mediated either through the guanylyl cyclase A receptor for atrial natriuretic peptide or through the gamma-adrenergic receptor, which is either itself a transmembrane guanylyl cyclase or activates a transmembrane guanylyl cyclase through cross-talk signaling.
authors.affiliation: Department of Biological Sciences, The University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, United Kingdom.
authors.forename: Rebecca C
authors.initials: RC
authors.lastname: Stratton
authors.affiliation: Department of Biological Sciences, The University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, United Kingdom.
authors.forename: Paul E
authors.initials: PE
authors.lastname: Squires
authors.affiliation: Department of Biological Sciences, The University of Warwick, Gibbet Hill Road, Coventry CV4 7AL, United Kingdom. Electronic address: A.K.Green@warwick.ac.uk.
authors.forename: Anne K
authors.initials: AK
authors.lastname: Green
mesh_terms: D000818:Animals; D009320:Atrial Natriuretic Factor / Q000037:antagonists & inhibitors / Q000494:pharmacology; D002118:Calcium / Q000378:metabolism*; D000252:Calcium-Transporting ATPases / Q000378:metabolism; D002462:Cell Membrane / Q000201:enzymology*; D002478:Cells, Cultured; D006152:Cyclic GMP / Q000378:metabolism*; D062965:Cyclic GMP-Dependent Protein Kinase Type I; D017869:Cyclic GMP-Dependent Protein Kinases / Q000378:metabolism*; D004336:Drug Antagonism; D004789:Enzyme Activation / Q000187:drug effects; D004958:Estradiol / Q000494:pharmacology*; D004967:Estrogens / Q000494:pharmacology*; D005260:Female; D006162:Guanylate Cyclase / Q000378:metabolism; D022781:Hepatocytes / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D011941:Receptors, Adrenergic / Q000378:metabolism
chemical_list: D004967:Estrogens; D011941:Receptors, Adrenergic; D004958:Estradiol; D009320:Atrial Natriuretic Factor; D062965:Cyclic GMP-Dependent Protein Kinase Type I; D017869:Cyclic GMP-Dependent Protein Kinases; D006162:Guanylate Cyclase; D000252:Calcium-Transporting ATPases; D006152:Cyclic GMP; D002118:Calcium