June 8, 2005 -- Researchers say there may be a link between estrogen deficiency and in men.
More than 3 million U.S. adults have OCD, says the National Institute of Mental Health. The disorder involves recurrent, unwanted thoughts or rituals such as counting, checking, cleaning, or washing the hands, which people feel they cannot control.
People with OCD can suffer intensely, but treatment is available. It's important to get help as soon as possible to improve quality of life.
OCD Behaviors Resolve With Estrogen
The findings are based on experiments with lab mice, not people.
Some of the mice in the study had a normal set of genes. Others were bred not to make an enzyme called aromatase, which converts male sex hormones to the female sex hormone estrogen. Because the genetically altered mice couldn't make aromatase, they had less estrogen than normal mice.
The results were presented in San Diego at The Endocrine Society's annual meeting.
The estrogen-deficient male mice stood out from the other mice in three ways:
- They ran "excessively" on their running wheels.
- They spent twice as long grooming themselves after being misted with water, compared with the other male mice.
- They had lower levels of a brain chemical called COMT (catechol-O-methyl transferase).
The extreme grooming and running patterns are two indicators of OCD in mice, and low COMT levels have been found in obsessive-compulsive men, say the researchers.
Treatment with estrogen reversed the excessive running and grooming behavior as well as raised COMT levels.
Estrogen-deficient female mice did not show the same patterns. That provides "further evidence" that estrogen affects the brains of males and females differently, say the researchers.