Neurosteroids and GABAergic signaling in health and disease

Autor: MacKenzie Georgina, Maguire Jamie
Jazyk: angličtina
Rok vydání: 2013
Předmět:
Zdroj: Biomolecular Concepts, Vol 4, Iss 1, Pp 29-42 (2013)
Druh dokumentu: article
ISSN: 1868-5021
1868-503X
DOI: 10.1515/bmc-2012-0033
Popis: Endogenous neurosteroids such as allopregnanolone, allotetrahydrodeoxycorticosterone, and androstanediol are synthesized either de novo in the brain from cholesterol or are generated from the local metabolism of peripherally derived progesterone or corticosterone. Fluctuations in neurosteroid concentrations are important in the regulation of a number of physiological responses including anxiety and stress, reproductive, and sexual behaviors. These effects are mediated in part by the direct binding of neurosteroids to γ-aminobutyric acid type-A receptors (GABAARs), resulting in the potentiation of GABAAR-mediated currents. Extrasynaptic GABAARs containing the δ subunit, which contribute to the tonic conductance, are particularly sensitive to low nanomolar concentrations of neurosteroids and are likely their preferential target. Considering the large charge transfer generated by these persistently open channels, even subtle changes in neurosteroid concentrations can have a major impact on neuronal excitability. Consequently, aberrant levels of neurosteroids have been implicated in numerous disorders, including, but not limited to, anxiety, neurodegenerative diseases, alcohol abuse, epilepsy, and depression. Here we review the modulation of GABAAR by neurosteroids and the consequences for health and disease.
Databáze: Directory of Open Access Journals