title: Enhancement by F-actin of MgATP-dependent dopamine uptake into isolated chromaffin granules.
abstract: Interaction of chromaffin granules with the microfilament network in the cytoplasmic space of adrenal medullary cells has been proposed, but the influence of chromaffin granule-microfilament interaction on granule function has not yet been studied. In the present study, the effect of F-actin on dopamine uptake into isolated chromaffin granules was examined. The MgATP-dependent component of dopamine uptake was significantly enhanced by F-actin. In contrast, catecholamine efflux from the granules was not significantly altered by F-actin under the conditions in which the enhancement of MgATP-dependent dopamine uptake was observed. These findings suggest that the interaction of chromaffin granules with the microfilament network results in the enhancement of MgATP-dependent dopamine uptake into the granules, thus modulating the accumulation and storage of catecholamines in the adrenal medullary cell.
authors.affiliation: Laboratory of Cell Biology and Genetics, National Institute of Diabetes, Digestive and Kidney Diseases, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors.forename: K
authors.initials: K
authors.lastname: Morita
authors.forename: S M
authors.initials: SM
authors.lastname: Tomares
authors.forename: H B
authors.initials: HB
authors.lastname: Pollard
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism; D000199:Actins / Q000378:metabolism*; D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D002395:Catecholamines / Q000378:metabolism; D002417:Cattle; D002837:Chromaffin Granules / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism*
chemical_list: D000199:Actins; D002395:Catecholamines; D000255:Adenosine Triphosphate; D004298:Dopamine