Lab study, 2005
How do changes in brain chemistry during the menstrual cycle affect anxiety and seizures?
During the high-progesterone phase of the cycle, specific brain chemicals increase the brain's ability to calm down, which reduces seizure risk and anxiety. Some women with PMDD or epilepsy may not have normal cycling of these chemicals, which could explain their symptoms.
What they did
Researchers studied mice and tracked changes in a specific brain receptor called GABA(A) receptors across the estrous cycle. They measured how effectively these receptors produced calming effects in brain cells and measured seizure susceptibility. They also tested what happened when they prevented normal cycling of these receptors using genetic techniques.
What they found
In the late diestrus phase (high-progesterone phase), there was increased expression of delta GABA(A)Rs, which increased calming effects in hippocampal neurons. This resulted in reduced seizure susceptibility and lower anxiety. When researchers prevented the cycling of these receptors using antisense RNA or gene knockout, this protective effect was lost.
What it means for you
Changes in specific brain chemicals during the menstrual cycle help protect against seizures and anxiety under normal conditions. Women with PMDD or certain types of epilepsy may have problems with how these chemicals normally cycle, which could explain why symptoms get worse before the period. This is animal research and needs to be tested in humans.
About the study
- Original title
- Ovarian cycle-linked changes in GABA(A) receptors mediating tonic inhibition alter seizure susceptibility and anxiety
- Authors
- Maguire JL, Stell BM, Rafizadeh M et al.
- Journal
- Nature neuroscience
- Year
- 2005
- Study design
- Lab study
- What was tested
- Genetic manipulation to prevent normal cycling of GABA receptors
- Read the paper
- doi.org/10.1038/nn1469
Topics
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