3α-Hydroxy-5α-pregnan-20-one exposure reduces GABAA receptor α4 subunit mRNA levels

doi:10.1016/S0014-2999(00)00797-4

European Journal of Pharmacology

Volume 409, Issue 2, 8 December 2000, Pages R1-R2

https://doi.org/10.1016/S0014-2999(00)00797-4 Get rights and content

Abstract

To examine the direct effects of neurosteroids on γ-aminobutyric acid type A (GABA_A) receptor expression, we exposed developing neuronal cells (P19) in vitro to 3α-hydroxy-5α-pregnan-20-one (3α,5α-THP, allopregnanolone). Quantitative reverse transcriptase-polymerase chain reaction (RT-PCR) analysis revealed a concentration-dependent decrease in GABA_A receptor α4 subunit mRNA expression that reversed 24 h after steroid withdrawal. These data suggest that variations in neurosteroid levels regulate the pattern of GABA_A receptor subunit expression and may alter the trophic effects of GABA.

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Acknowledgements

The authors are grateful to Margaret J. VanDoren for 3α,5α-THP level determinations in culture media. The present work was supported by the National Institute on Alcohol Abuse and Alcoholism grant AA09013.

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Rapid communication3α-Hydroxy-5α-pregnan-20-one exposure reduces GABAA receptor α4 subunit mRNA levels

Abstract

Section snippets

Acknowledgements

Brain Res. Dev. Brain Res.

Brain Res. Mol. Brain Res.

GABA stimulates chemotaxis and chemokinesis of embryonic cortical neurons via calcium-dependent mechanisms

J. Neurosci.

Role of brain allopregnanolone in the plasticity of gamma-aminobutyric acid type A receptor in rat brain during pregnancy and after delivery

Proc. Natl. Acad. Sci. U. S. A.

Rapid communication
3α-Hydroxy-5α-pregnan-20-one exposure reduces GABA_A receptor α4 subunit mRNA levels