title: Stimulation of secretion from bovine adrenal chromaffin cells by microsecond bursts of therapeutic levels of ultrasound.
abstract: 1. In this study the secretory response of individual bovine adrenal chromaffin cells was monitored using amperometric carbon-fibre microelectrodes. Cells were stimulated to secrete by exposure to 20-100 microseconds long tonebursts of ultrasound (2-4 x 10(5) Pa; peak pressure at 1 MHz). 2. Three types of secretory responses were observed: an almost instantaneous response, a delayed release of catecholamines, or a series of 'burst-like' secretory bouts. 3. Fura-2 measurements of intracellular Ca2+ concentrations showed that the release of catecholamines was accompanied by an increase in the intracellular Ca2+ concentration. In the absence of extracellular Ca2+, secretory responses were not evoked showing that Ca2+ entry was necessary to elicit catecholamine release.
authors.affiliation: Department of Physiology and Biophysics, Mayo Foundation, Rochester, MN 55905, USA.
authors.forename: I M
authors.initials: IM
authors.lastname: Robinson
authors.forename: R R
authors.initials: RR
authors.lastname: Kinnick
authors.forename: J F
authors.initials: JF
authors.lastname: Greenleaf
authors.forename: J M
authors.initials: JM
authors.lastname: Fernandez
mesh_terms: D000311:Adrenal Glands / Q000378:metabolism*; D000818:Animals; D002118:Calcium / Q000378:metabolism; D002395:Catecholamines / Q000378:metabolism; D002417:Cattle; D002478:Cells, Cultured; D002838:Chromaffin System / Q000378:metabolism*; D016257:Fura-2 / Q000494:pharmacology; D014464:Ultrasonic Therapy
chemical_list: D002395:Catecholamines; D002118:Calcium; D016257:Fura-2