title: Swelling-induced catecholamine secretion recorded from single chromaffin cells.
abstract: We have studied osmotically induced catecholamine secretion from bovine adrenal chromaffin cells by combining patch-clamp measurements, electrochemical detection of secretion, and Fura-2 measurements of intracellular free calcium concentration ([Ca2+]i). We find that osmotically induced catecholamine release is exocytotic and calcium dependent. Furthermore, we demonstrate that cell swelling is coupled to such secretion via a volume-activated current, carrying predominantly chloride, which causes a plateau depolarization of the cell membrane potential and thus promotes voltage-activated calcium influx. Therefore, cell volume changes may modulate the secretory activity.
authors.affiliation: Abteilung Membranbiophysik, Max-Planck-Institut für Biophysikalische Chemie, Göttingen, Germany.
authors.forename: T
authors.initials: T
authors.lastname: Moser
authors.forename: R H
authors.initials: RH
authors.lastname: Chow
authors.forename: E
authors.initials: E
authors.lastname: Neher
mesh_terms: D000818:Animals; D002395:Catecholamines / Q000378:metabolism*; D002417:Cattle; D048429:Cell Size / Q000502:physiology; D002478:Cells, Cultured; D002838:Chromaffin System / Q000166:cytology / Q000378:metabolism*; D004594:Electrophysiology; D005089:Exocytosis / Q000502:physiology; D016257:Fura-2; D008564:Membrane Potentials / Q000502:physiology; D009994:Osmolar Concentration; D018408:Patch-Clamp Techniques
chemical_list: D002395:Catecholamines; D016257:Fura-2