Atrial natriuretic peptide attenuates Ca2+ oscillations and modulates plasma membrane Ca2+ fluxes in rat hepatocytes
UNSPECIFIED. (2002) Atrial natriuretic peptide attenuates Ca2+ oscillations and modulates plasma membrane Ca2+ fluxes in rat hepatocytes. GASTROENTEROLOGY, 123 (4). pp. 1291-1303. ISSN 0016-5085Full text not available from this repository.
Official URL: http://dx.doi.org/10.1053/gast.2002.35994
Bacground & Aims: Oscillations in cytosolic free Ca2+ concentration are a fundamental mechanism of intracellular signaling in hepatocytes. The aim of this study was to examine the effects of atrial natriuretic peptide (ANP) on cytosolic Ca2+ oscillations in rat hepatocytes. Methods: Cyclic guanosine monophosphate (cGMP) was measured by enzyme immunoassay. Cytosolic Ca2+ oscillations were recorded from single aequorin-injected hepatocytes. Ca2+ efflux from hepatocyte populations was measured by using extracellular fura-2. Ca2+ influx was estimated by Mn2+ quench of fluorescence of fura-2 dextran injected into single hepatocytes. Results: ANP attenuated cytosolic Ca2+ oscillations through a decrease in their frequency. In addition, ANP dramatically stimulated plasma membrane Ca2+ efflux and modestly inhibited basal Ca2+ influx. All of the observed effects of ANP were mimicked by the cGMP analogue 8-bromo-cGMP (S-Br-cGMP), and were prevented by inhibition of protein kinase G. In contrast, activation of cytosolic guanylyl cyclase by sodium nitroprusside had no effect on Ca2+ efflux, Ca2+ influx, or Ca2+ oscillations. Conclusions: ANP decreases the frequency of Ca2+ oscillations and modulates plasma membrane Ca2+ fluxes in rat hepatocytes. Attenuation of oscillatory Ca2+ Signaling in hepatocytes may represent a key role for ANP in vivo.
|Item Type:||Journal Article|
|Subjects:||R Medicine > RC Internal medicine|
|Journal or Publication Title:||GASTROENTEROLOGY|
|Publisher:||W B SAUNDERS CO|
|Number of Pages:||13|
|Page Range:||pp. 1291-1303|
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