Lab study, 2006
Can a hormone that usually reduces anxiety instead cause anxiety after your body adapts to its being blocked?
Yes. When a hormone precursor was blocked, the hormone THP (which normally calms anxiety) instead increased anxiety in female mice. This effect involved changes to specific brain receptors.
What they did
Researchers gave female mice a drug called finasteride for 3 days to block production of a steroid hormone. Then they tested the mice in a maze where anxious mice avoid open spaces. They also measured changes in brain receptors to see what had changed.
What they found
After hormone blockade, THP caused anxiety instead of reducing it. The mice avoided open spaces more than expected. The researchers found increased levels of a specific brain receptor (alpha4 subunit) in the hippocampus. When they tested mice lacking this receptor type, the anxiety effects disappeared.
What it means for you
Changes in brain receptors from low hormone levels might flip how certain hormones and drugs affect anxiety, which could explain some PMDD symptoms. The brain receptor change might be a key mechanism. This is a laboratory mouse study modeling one possible mechanism in PMDD, but not a study of women with the disorder.
3 days
finasteride treatment
About the study
- Original title
- Steroid withdrawal in the mouse results in anxiogenic effects of 3alpha,5beta-THP: a possible model of premenstrual dysphoric disorder
- Authors
- Smith SS, Ruderman Y, Frye C et al.
- Journal
- Psychopharmacology
- Year
- 2006
- Study design
- Lab study
- What was tested
- Finasteride to block hormone production, then THP and other drugs
- Open access
- Yes
- Read the paper
- doi.org/10.1007/s00213-005-0168-3
Topics
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