GABA(A) receptor function and gene expression during pregnancy and postpartum.
Giovanni Biggio1, Maria Cristina Mostallino, Paolo Follesa
1Department of Experimental Biology, Center of Excellence for the Neurobiology of Dependence, University of Cagliari, 09100 Cagliari, Italy.
International Review of Neurobiology
|July 18, 2009
Summary
Pregnancy elevates neuroactive steroids, altering GABA(A) receptors in the brain. These changes in GABA(A)-receptor gene expression and function may influence mood and anxiety during pregnancy.
Area of Science:
- Neuroscience
- Neuroendocrinology
- Molecular Psychiatry
Background:
- Neuroactive steroids, such as 3alpha,5alpha-THP, are progesterone metabolites that modulate neuronal excitability.
- GABA(A) receptors (GABA(A)-Rs) mediate inhibitory neurotransmission, with distinct synaptic and extrasynaptic subtypes.
- Extrasynaptic GABA(A)-Rs, rich in delta subunits, are more sensitive to neuroactive steroids.
Purpose of the Study:
- To review findings on the impact of pregnancy-induced neuroactive steroid changes on GABA(A)-Rs.
- To explore the relationship between neurosteroid fluctuations and potential mood/anxiety alterations.
Main Methods:
- Utilizing a rat model of pregnancy.
- Analyzing changes in neuroactive steroid levels during pregnancy.
- Assessing alterations in GABA(A)-R gene expression and function in the hippocampus and other brain areas.
Main Results:
- Pregnancy is associated with progressive increases in plasma and brain neuroactive steroid levels.
- Elevated neuroactive steroids during pregnancy correlate with changes in both synaptic and extrasynaptic GABA(A)-R expression and function.
- These alterations occur in the hippocampus and other brain regions.
Conclusions:
- Neuroactive steroid fluctuations during pregnancy significantly impact GABA(A)-R plasticity.
- Changes in GABA(A)-R function may underlie pregnancy-related mood and anxiety variations.
- Further research is warranted to elucidate the precise mechanisms and clinical implications.
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