Compulsive hoarding
Obsessive-compulsive disorders are treated with various serotonergic antidepressants including the tricyclic antidepressant clomipramine and various SSRI medications. With existing drug therapy, OCD symptoms can be controlled, but not cured. Several of these compounds (including paroxetine, which has an FDA indication) have been tested successfully in conjunction with OCD hoarding.
Estrogen
Compulsions in male lab mice, such as those in obsessive-compulsive disorder (OCD), may be caused by low estrogen levels. When estrogen levels were raised through the increased activity of the enzyme aromatase in male lab mice, OCD rituals were dramatically decreased. Hypothalamic protein levels in the gene COMT are enhanced by increasing estrogen levels which are believed to return mice that displayed OCD rituals to normal activity. Aromatase deficiency is ultimately suspected which is involved in the synthesis of estrogen in humans and has therapeutic implications in humans having obsessive-compulsive disorder.