|
|
||||||||
AJP - Cell Physiology, Vol 267, Issue 5 C1246-C1252, Copyright © 1994 by American Physiological Society
ARTICLES |
T. Rohacs, A. Bago, F. Deak, L. Hunyady and A. Spat
Department of Physiology, Semmelweis University of Medicine, Budapest, Hungary.
We examined the effect of the depletion of intracellular Ca2+ stores on Ca2+ influx in rat glomerulosa cells. Depletion of intracellular Ca2+ stores was achieved by inhibiting sarco/endoplasmic reticulumtype Ca(2+)-ATPase with thapsigargin or 2,5,di-(t-butyl)-1,4-benzohydroquinone (t-BHQ). Both inhibitors induced a sustained rise in cytoplasmic Ca2+ concentration. The initial rise was observed also in Ca(2+)-free medium, while the sustained phase disappeared, indicating that the latter requires Ca2+ influx. In Ca(2+)-free medium, the readdition of Ca2+ induced a steeper and higher rise in intracellular Ca2+ concentration in thapsigargin-treated cells than in controls, supporting the role of Ca2+ influx. In normal medium, the addition of Cd2+ (80 microM) evoked an immediate inhibition of the sustained phase of thapsigargin response. The response to thapsigargin was insensitive to nifedipine. Thapsigargin failed to enhance Mn2+ quenching of fura 2. Our results provide evidence for the existence of capacitative Ca2+ influx in rat glomerulosa cells and indicate that dihydropyridine-sensitive Ca2+ channels do not participate in capacitative Ca2+ entry. High concentrations of thapsigargin and t-BHQ, similar to the reported effects of angiotensin II and vasopressin, inhibited K(+)-induced Ca2+ signals. These effects appear, however, to be independent of the depletion of internal Ca2+ stores.
This article has been cited by other articles:
![]() |
A. B. Parekh and J. W. Putney Jr. Store-Operated Calcium Channels Physiol Rev, April 1, 2005; 85(2): 757 - 810. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. SPAT and L. HUNYADY Control of Aldosterone Secretion: A Model for Convergence in Cellular Signaling Pathways Physiol Rev, April 1, 2004; 84(2): 489 - 539. [Abstract] [Full Text] [PDF] |
||||
![]() |
X.-L. Chen, D. A. Bayliss, R. J. Fern, and P. Q. Barrett A role for T-type Ca2+ channels in the synergistic control of aldosterone production by ANG II and K+ Am J Physiol Renal Physiol, May 1, 1999; 276(5): F674 - F683. [Abstract] [Full Text] [PDF] |
||||
![]() |
M. F. Rossier, E. A. Ertel, M. B. Vallotton, and A. M. Capponi Inhibitory Action of Mibefradil on Calcium Signaling and Aldosterone Synthesis in Bovine Adrenal Glomerulosa Cells J. Pharmacol. Exp. Ther., December 1, 1998; 287(3): 824 - 831. [Abstract] [Full Text] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |