Ca2+ influx and clearance at hyperpolarized membrane potentials modulate spontaneous and stimulated exocytosis in neuroendocrine cells.

Cell Calcium
Lukun Yang, A F Fomina

Abstract

Neuroendocrine adrenal chromaffin cells release neurohormones catecholamines in response to Ca2+ entry via voltage-gated Ca2+ channels (VGCCs). Adrenal chromaffin cells also express non-voltage-gated channels, which may conduct Ca2+ at negative membrane potentials, whose role in regulation of exocytosis is poorly understood. We explored how modulation of Ca2+ influx at negative membrane potentials affects basal cytosolic Ca2+ concentration ([Ca2+]i) and exocytosis in metabolically intact voltage-clamped bovine adrenal chromaffin cells. We found that in these cells, Ca2+ entry at negative membrane potentials is balanced by Ca2+ extrusion by the Na+/Ca2+ exchanger and that this balance can be altered by membrane hyperpolarization or stimulation with an inflammatory hormone bradykinin. Membrane hyperpolarization or application of bradykinin augmented Ca2+-carrying current at negative membrane potentials, elevated basal [Ca2+]i, and facilitated synchronous exocytosis evoked by the small amounts of Ca2+ injected into the cell via VGCCs (up to 20 pC). Exocytotic responses evoked by the injections of the larger amounts of Ca2+ via VGCCs (> 20 pC) were suppressed by preceding hyperpolarization. In the absence of Ca2+ entry via VGCCs an...Continue Reading

References

May 1, 1992·The Journal of Physiology·E Neher, G J Augustine
Jul 1, 1991·Cell Calcium·D A PowisH R Von Grafenstein
Apr 1, 1993·Pflügers Archiv : European journal of physiology·A R ArtalejoE Neher
Dec 31, 1997·The Journal of Cell Biology·C Smith, E Neher
Nov 20, 1998·The Biochemical Journal·C Y PanL S Kao
Oct 12, 2000·Biophysical Journal·F D Marengo, J R Monck
Feb 22, 2002·The Journal of Biological Chemistry·Alexander G Obukhov, Martha C Nowycky
May 3, 2002·The Journal of Physiology·Damian J WallacePhilip D Marley
Oct 26, 2002·Science·Jens Rettig, Erwin Neher
Apr 2, 2003·Pharmacology & Therapeutics·Philip D Marley
Feb 25, 2005·Journal of Cellular Physiology·Kazuhiro ShimazuGordon Guroff
Oct 4, 2006·Physiological Reviews·Antonio G GarcíaJavier García-Sancho
Aug 23, 2008·Journal of Neurochemistry·Chien-Yuan PanLung-Sen Kao
Dec 17, 2009·Journal of Neurochemistry·Pei-Chun WuLung-Sen Kao
Sep 24, 2010·Cold Spring Harbor Perspectives in Biology·Maarten GeesBernd Nilius
Feb 5, 2011·American Journal of Physiology. Gastrointestinal and Liver Physiology·Mark K Lukewich, Alan E Lomax
Mar 23, 2011·Frontiers in Synaptic Neuroscience·David R StevensJens Rettig
Jun 30, 2012·American Journal of Physiology. Cell Physiology·Masumi InoueAkira Warashina
Apr 19, 2013·American Journal of Physiology. Cell Physiology·Juan-Fernando PadínAntonio G García

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