Lab study, 2005
When progesterone drops during the menstrual cycle, do brain changes occur that could explain anxiety in PMDD?
Yes, according to this rat study. When progesterone was withdrawn, a specific type of brain receptor involved in anxiety control increased dramatically in numbers in key brain regions.
What they did
Laboratory study in adult female rats. Three groups were compared: rats given progesterone continuously for 7 days, rats that received progesterone for 6 days then were withdrawn from it for 24 hours, and control rats. Brain tissue was examined to count changes in receptors in the brain region controlling panic and anxiety.
What they found
Rats going through progesterone withdrawal had significantly higher numbers of GABA(A) receptors (the alpha4-beta1-delta type) compared to rats on progesterone or controls. The increase was most pronounced in one specific brain area involved in panic responses. The parallel increase in all three receptor components suggests they work together as a unit when progesterone falls.
What it means for you
When progesterone drops during your cycle, your brain's chemistry changes in ways that might increase anxiety and panic. This could help explain why women with PMDD have worse anxiety during the premenstrual phase. However, this finding is from rats, not yet proven in people. More research is needed to determine if this mechanism applies to women.
6 days
Duration of progesterone treatment
24 hours
Withdrawal period
7 days
Continuous progesterone duration
About the study
- Original title
- Withdrawal from progesterone increases expression of alpha4, beta1, and delta GABA(A) receptor subunits in neurons in the periaqueductal gray matter in female Wistar rats
- Authors
- Griffiths J, Lovick T
- Journal
- The Journal of comparative neurology
- Year
- 2005
- Study design
- Lab study
- What was tested
- Progesterone withdrawal
- Read the paper
- doi.org/10.1002/cne.20540
Topics
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