en
Scientific article
English

Control of cytosolic free calcium by intracellular organelles in bovine adrenal glomerulosa cells. Effects of sodium and inositol 1,4,5-trisphosphate

Published inThe Journal of biological chemistry, vol. 262, no. 9, p. 4053-4058
Publication date1987
Abstract

The regulation of cytosolic free Ca2+ concentration ([Ca2+]c) by intracellular organelles was studied in permeabilized bovine adrenal glomerulosa cells. Two compartments, with distinct characteristics, were able to pump Ca2+. A first pool, sensitive to ruthenium red and presumably mitochondrial, required respiratory chain substrates to maintain [Ca2+]c around 700 nM. Ca2+ efflux from this compartment was activated by Na+ (ED50 = 5 mM). Inositol 1,4,5-trisphosphate (IP3) had no effect on this pool. A second nonmitochondrial pool required ATP to lower [Ca2+]c to about 200 nM and released Ca2+ transiently upon addition of IP3. When the two systems were allowed to work simultaneously, the nonmitochondrial pool regulated [Ca2+]c and IP3 released Ca2+ in a concentration-dependent manner (EC50 = 0.6 microM). Under these conditions the mitochondria seemed Ca2+ depleted. Upon repeated stimulations with IP3, a marked attenuation of the response was observed. This phenomenon was due to Ca2+ sequestration by a nonmitochondrial IP3-insensitive pool. Neither dantrolene (200 microM) nor 8-(N,N-diethylamino)octyl-3,4,5-trimethoxybenzoate (10 microM) were able to abolish IP3-induced Ca2+ release, though both compounds efficiently inhibited aldosterone production in intact cells stimulated with angiotensin II (10 nM) or K+ (12 mM). These results suggest that in permeabilized adrenal glomerulosa cells: the nonmitochondrial pool is responsible for buffering [Ca2+]c and for releasing Ca2+ in response to IP3; at resting [Ca2+]c levels, the mitochondria appear Ca2+ depleted; when [Ca2+]c rises above their set point, the mitochondria accumulate Ca2+ as a function of [Na+]c; 4) the mitochondria are not involved in the desensitization mechanism of the response to IP3.

Keywords
  • Adenosine Triphosphate/pharmacology
  • Adrenal Glands/drug effects/ ultrastructure
  • Animals
  • Calcium/ metabolism
  • Cattle
  • Cell Membrane Permeability
  • Dantrolene/pharmacology
  • Gallic Acid/analogs & derivatives/pharmacology
  • Inositol 1,4,5-Trisphosphate
  • Inositol Phosphates/ pharmacology
  • Magnesium/pharmacology
  • Mitochondria/drug effects/metabolism
  • Organoids/ metabolism
  • Ruthenium Red/pharmacology
  • Sodium/pharmacology
  • Sugar Phosphates/ pharmacology
Citation (ISO format)
ROSSIER, M. F. et al. Control of cytosolic free calcium by intracellular organelles in bovine adrenal glomerulosa cells. Effects of sodium and inositol 1,4,5-trisphosphate. In: The Journal of biological chemistry, 1987, vol. 262, n° 9, p. 4053–4058.
Main files (1)
Article
accessLevelRestricted
Identifiers
ISSN of the journal0021-9258
485views
0downloads

Technical informations

Creation08/27/2010 1:36:02 PM
First validation08/27/2010 1:36:02 PM
Update time03/14/2023 4:05:06 PM
Status update03/14/2023 4:05:06 PM
Last indexation02/12/2024 7:23:28 PM
All rights reserved by Archive ouverte UNIGE and the University of GenevaunigeBlack