Anorexia and dopamine

Overactive dopamine receptors may help explain anorexia nervosa symptoms.

Since other studies have found reduced binding of these dopamine receptors in both people who are obese and those who have substance use problems, Drs. Kaye and Frank hypothesized that they would find just the opposite in women with anorexia.

Indeed, there was increased receptor binding in the basal ganglia's antero-ventral striatum in the women with a history of anorexia nervosa irrespective of their age, body mass index or time since recovery, but not in any of the healthy women. The antero-ventral striatum is an area known to modulate reward and reinforcement and is therefore important in learning from experience.

The researchers also found increased dopamine D2/D3 receptor activity in another part of the basal ganglia called the dorsal caudate, which is related to responses to and avoidance of harm. Such activity may help explain why women with anorexia exhibit exaggerated worry and concern about what might happen in the future.http://www.news-medical.net/news/2005/07/11/11621.aspx