Dataset Information

Ethanol withdrawal-induced dysregulation of neurosteroid levels in plasma, cortex, and hippocampus in genetic animal models of high and low withdrawal.

ABSTRACT:

Rationale

Endogenous γ-aminobutyric acid_A receptor (GABA_AR)-active neurosteroids (e.g., allopregnanolone) regulate central nervous system excitability and many physiological functions, so fluctuations are implicated in several neuropsychiatric disorders. Pertinently, evidence supports an inverse relationship between endogenous GABA_AR-active neurosteroid levels and behavioral changes in excitability during ethanol withdrawal (WD).

Objectives

The present studies determined mouse genotype differences in ten neurosteroid levels in plasma, cortex, and hippocampus over the time course of ethanol WD in the WD Seizure-Prone (WSP) and WD Seizure-Resistant (WSR) selected lines and in the DBA/2J (DBA) inbred strain.

Methods

Gas chromatography-mass spectrometry was utilized to simultaneously quantify neurosteroid levels from control-treated male WSP-1, WSR-1, and DBA mice and during 8 and 48 h of WD.

Results

Combined with our prior work, there was a consistent decrease in plasma allopregnanolone levels at 8 h WD in all three genotypes, an effect that persisted at 48 h WD only in DBA mice. WSR-1 and WSP-1 mice exhibited unexpected divergent changes in cortical neurosteroids at 8 h WD, with the majority of neurosteroids (including allopregnanolone) being significantly decreased in WSR-1 mice, but unaffected or significantly increased in WSP-1 mice. In DBA mice, hippocampal allopregnanolone and tetrahydrodeoxycorticosterone were significantly decreased at 8 h WD. The pattern of significant correlations between allopregnanolone and other GABA_AR-active neurosteroid levels differed between controls and withdrawing mice.

Conclusions

Ethanol WD dysregulated neurosteroid synthesis. Results in WSP-1 mice suggest that diminished GABA_AR function is more important for their high WD phenotype than fluctuations in neurosteroid levels.

SUBMITTER: Jensen JP

PROVIDER: S-EPMC5990276 | biostudies-literature | 2017 Sep

REPOSITORIES: biostudies-literature

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Publications

Ethanol withdrawal-induced dysregulation of neurosteroid levels in plasma, cortex, and hippocampus in genetic animal models of high and low withdrawal.

Jensen Jeremiah P JP Nipper Michelle A MA Helms Melinda L ML Ford Matthew M MM Crabbe John C JC Rossi David J DJ Finn Deborah A DA

Psychopharmacology 20170629 18

<h4>Rationale</h4>Endogenous γ-aminobutyric acid<sub>A</sub> receptor (GABA<sub>A</sub>R)-active neurosteroids (e.g., allopregnanolone) regulate central nervous system excitability and many physiological functions, so fluctuations are implicated in several neuropsychiatric disorders. Pertinently, evidence supports an inverse relationship between endogenous GABA<sub>A</sub>R-active neurosteroid levels and behavioral changes in excitability during ethanol withdrawal (WD).<h4>Objectives</h4>The pre ...[more]

PMID: 28664280

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Dataset Information

Ethanol withdrawal-induced dysregulation of neurosteroid levels in plasma, cortex, and hippocampus in genetic animal models of high and low withdrawal.

Rationale

Objectives

Methods

Results

Conclusions

Publications

Ethanol withdrawal-induced dysregulation of neurosteroid levels in plasma, cortex, and hippocampus in genetic animal models of high and low withdrawal.

Similar Datasets

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