QUICK SEARCH:   [advanced] Author: Keyword(s): Year:  Vol:  Page:

HOME  |   SEARCH  |   ARCHIVE  |   SUBSCRIBE  |   CONTACT  |   HELP

This Article Full Text (PDF) Submit an eLetter Alert me when this article is cited Alert me when eLetters are posted Alert me if a correction is posted Citation Map Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via HighWire Citing Articles via Web of Science (31) Citing Articles via Google Scholar Google Scholar Articles by Dayanithi, G. Articles by Tapia-Arancibia, L. Search for Related Content PubMed PubMed Citation Articles by Dayanithi, G. Articles by Tapia-Arancibia, L. Pubmed/NCBI databases Compound via MeSH Substance via MeSH Hazardous Substances DB CALCIUM COMPOUNDS CALCIUM, ELEMENTAL PICROTOXIN

 Previous Article  |  Next Article 

Journal of Neuroscience, Vol 16, 130-136, Copyright © 1996 by Society for Neuroscience

ARTICLE

Rise in intracellular calcium via a nongenomic effect of allopregnanolone in fetal rat hypothalamic neurons

G Dayanithi and L Tapia-Arancibia
Laboratoire de Neurobiologie Endocrinologique, URA 1197 CNRS, Universite Montpellier II, France.

This study examines the early effects of 3 alpha-hydroxy-5 alpha- pregnan-20-one (allopregnanolone on cytosolic free calcium concentration ([Ca2+]i in primary cultures of fetal rat hypothalamic neurons. Microspectrofluorimetry of fluorescent Ca2+(-)sensitive indicator Fura-2 was used to quantify these changes. Allopregnanolone (1 pM to 100 nM) increased [Ca2+]i within 2-3 sec, in a dose dependent manner, with an EC50 of 10 +/- 4 nM. The stimulatory effect of allopregnanolone was attributable principally to a Ca2+ influx, as shown by the strong inhibition of external Ca2+ removal or by the calcium channel blocker nifedipine. The effect was stereospecific because the allopregnanolone isomer 3 beta-hydroxy-5 alpha-pregnan-20- one had no effect on [Ca2+]i. Among two other steroids examined, progesterone had no effect on [Ca2+]i, but 17 beta-estradiol evoked a rise in [Ca2+]i, although to a lesser extent than allopregnanolone. The allopregnanolone-induced [Ca2+]i rise was inhibited by picrotoxin and bicuculline but was unaffected by tetrodotoxin or by pretreatment of neurons with pertussis toxin. These results are consistent with a membrane site of action for allopregnanolone associated with GABAA receptors, leading to rapid changes in [Ca2+]i in fetal rat hypothalamic neurons.

This article has been cited by other articles:

				J. M. Wang, P. B. Johnston, B. G. Ball, and R. D. Brinton The Neurosteroid Allopregnanolone Promotes Proliferation of Rodent and Human Neural Progenitor Cells and Regulates Cell-Cycle Gene and Protein Expression J. Neurosci., May 11, 2005; 25(19): 4706 - 4718. [Abstract] [Full Text] [PDF]

				V. V. Chaban, A. J. Lakhter, and P. Micevych A Membrane Estrogen Receptor Mediates Intracellular Calcium Release in Astrocytes Endocrinology, August 1, 2004; 145(8): 3788 - 3795. [Abstract] [Full Text] [PDF]

				H. Widmer, M. Ludwig, F. Bancel, G. Leng, and G. Dayanithi Neurosteroid regulation of oxytocin and vasopressin release from the rat supraoptic nucleus J. Physiol., April 1, 2003; 548(1): 233 - 244. [Abstract] [Full Text] [PDF]

				A. Fancsik, D. M. Linn, and J. G. Tasker Neurosteroid Modulation of GABA IPSCs Is Phosphorylation Dependent J. Neurosci., May 1, 2000; 20(9): 3067 - 3075. [Abstract] [Full Text] [PDF]

				E. J Cooper, G. A R Johnston, and F. A Edwards Effects of a naturally occurring neurosteroid on GABAA IPSCs during development in rat hippocampal or cerebellar slices J. Physiol., December 1, 1999; 521(2): 437 - 449. [Abstract] [Full Text] [PDF]

				M. Christ, A. Gunther, M. Heck, B. M. W. Schmidt, E. Falkenstein, and M. Wehling Aldosterone, Not Estradiol, Is the Physiological Agonist for Rapid Increases in cAMP in Vascular Smooth Muscle Cells Circulation, March 23, 1999; 99(11): 1485 - 1491. [Abstract] [Full Text] [PDF]

Home  |   Search  |   Archive  |   Subscribe  |   Contact  |   Help