Survey study, 2001
Does short-term progesterone exposure change anxiety and brain chemistry in female rats?
Yes. Even 2-3 days of progesterone exposure changed brain cell receptors in a way linked to increased anxiety, and rats showed more anxiety-like behavior.
What they did
Female rats were exposed to progesterone for different lengths of time. Researchers measured changes in a specific brain cell part called the alpha4 subunit in the hippocampus and tested anxiety-like behavior by observing how much rats avoided open spaces.
What they found
After 2-3 days of progesterone, the alpha4 receptor increased 2 to 3 times, and this was linked to near total loss of response to anti-anxiety medicine. Anxiety-like behavior increased by 72 hours of hormone exposure. After 5-6 days of continued progesterone, the alpha4 receptor returned to normal levels and anxiety improved.
What it means for you
Short-term hormonal changes can quickly alter brain chemistry and increase anxiety. The brain returns to normal as hormone exposure continues. This is an animal study, so we cannot directly apply it to humans, but it may help explain why some women experience anxiety changes during their menstrual cycle.
2-3 days
progesterone exposure for maximum alpha4 increase
2 to 3 fold
increase in alpha4 receptor levels
72 hours
time of peak anxiety-like behavior
About the study
- Original title
- Short-term exposure to a neuroactive steroid increases alpha4 GABA(A) receptor subunit levels in association with increased anxiety in the female rat
- Authors
- Gulinello M, Gong QH, Li X et al.
- Journal
- Brain research
- Year
- 2001
- Study design
- Survey study
- What was tested
- Progesterone exposure
- Open access
- Yes
- Read the paper
- doi.org/10.1016/s0006-8993(01)02565-3
Topics
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