THE appetite-suppressing side effect of ecstasy may reveal why people with anorexia nervosa can lose the physical urge to eat, despite really needing the energy.
Valerie Compan at the national centre for scientific research in Montpelier, France, and her colleagues wondered if the brain's reward centre--the nucleus accumbens (NAcc), which is stimulated by ecstasy--might also play a role in anorexia.
They stimulated serotonin-4 receptors in the NAcc of mice, which reduced their urge to eat, but also boosted levels of a peptide called CART in the animals' brains. CART levels are also higher in the blood of anorexic women, and drugs like ecstasy are also known to raise CART levels in people.
Blocking the production of CART increased appetite, the team found. And when mice genetically engineered to lack serotonin-4 receptors were given ecstasy, they ate normally, suggesting ecstasy affects appetite through these receptors (Proceedings of the National Academy of Sciences, DOI: 10.1073/pnas0701471104).
Compan says the research emphasises that anorexia is more than psychological, and may point to drug targets for its treatment.