Endocrinology, Vol 137, 4331-4338, Copyright © 1996 by Endocrine Society

ARTICLES

Induction of steroidogenic enzymes by potassium in cultured rat zona glomerulosa cells depends on calcium influx and intact protein synthesis

A Yagci and J Muller
Department of Internal Medicine, University Hospital, Zurich, Switzerland.

The effects of a calcium channel blocker (nifedipine) and a protein synthesis inhibitor (cycloheximide) on the induction of four steroidogenic cytochromes P450 (CYP11B2, CYP11B1, CYP11A1, and CYP21A1) by an elevated extracellular potassium concentration were studied in cultured rat zona glomerulosa cells. Each of these two pharmacological agents completely inhibited the initiation of CYP11B2 expression and aldosterone biosynthesis in response to a high extracellular potassium concentration (18 mM). They also suppressed the potassium-induced increases in CYP11B1, CYP11A1, and CYP21A1 messenger RNA levels. Increases of these latter parameters elicited by ACTH were also suppressed by cycloheximide but were not affected by nifedipine. According to these experiments, calcium is an important second messenger mediating the effects of a high extra-cellular potassium concentration on the expression of genes encoding steroidogenic enzymes in rat zona glomerulosa cells. Because these effects also depend on an intact protein synthesis, an unknown labile regulatory protein seems to play an important role in the intracellular signal transmission from the plasma membrane to the genome.

This article has been cited by other articles:

				H.-W. Chang, V.-C. Wu, C.-Y. Huang, H.-Y. Huang, Y.-M. Chen, T.-S. Chu, K.-D. Wu, and B.-S. Hsieh D4 dopamine receptor enhances angiotensin II-stimulated aldosterone secretion through PKC-{varepsilon} and calcium signaling Am J Physiol Endocrinol Metab, March 1, 2008; 294(3): E622 - E629. [Abstract] [Full Text] [PDF]

				H.-W. Chang, T.-S. Chu, H.-Y. Huang, S.-C. Chueh, V.-C. Wu, Y.-M. Chen, B.-S. Hsieh, and K.-D. Wu Down-Regulation of D2 Dopamine Receptor and Increased Protein Kinase C{micro} Phosphorylation in Aldosterone-Producing Adenoma Play Roles in Aldosterone Overproduction J. Clin. Endocrinol. Metab., May 1, 2007; 92(5): 1863 - 1870. [Abstract] [Full Text] [PDF]

				B. Peters, P. Teubner, S. Clausmeyer, T. Puschner, C. Maser-Gluth, H.-J. Wrede, B. Kranzlin, and J. Peters StAR expression and the long-term aldosterone response to high-potassium diet in Wistar-Kyoto and spontaneously hypertensive rats Am J Physiol Endocrinol Metab, January 1, 2007; 292(1): E16 - E23. [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]

				J. C. Condon, V. Pezzi, B. M. Drummond, S. Yin, and W. E. Rainey Calmodulin-Dependent Kinase I Regulates Adrenal Cell Expression of Aldosterone Synthase Endocrinology, September 1, 2002; 143(9): 3651 - 3657. [Abstract] [Full Text] [PDF]