August 11, 1995
Media Contact: John Cramer
Phone: (410) 955-1534
The recreational drug Ecstasy, already suspected of causing brain damage, may do lasting harm by causing key nerve cells in the brain to grow back abnormally, according to results of a Johns Hopkins animal study.
The findings support earlier indications that the drug MDMA, often called Ecstasy, may cause lasting damage to nerves that produce serotonin, an important chemical messenger in the human brain associated with mood and personality traits.
The findings are published in the August issue of Journal of Neuroscience.
"MDMA causes an abnormal regeneration, or rewiring, of the nerve cells that release serotonin," says George Ricaurte, M.D., Ph.D., the study's senior author and assistant professor of neurology at The Johns Hopkins Medical Institutions. "The results are further evidence that people using high doses of MDMA may be putting themselves at significant risk for brain injury."
In a 1994 study, Ricaurte led the first controlled human study with MDMA. The results suggested MDMA users were vulnerable to the same type of brain damage shown previously in animal studies. But researchers did not know if the damaged serotonin nerve cells eventually recovered.
Results of the current study showed that the damaged cells recovered abnormally in most of the monkeys and a few of the rats 12 to 18 months after they received the drug. The cells recovered in some areas, but in other areas the serotonin nerve fibers did not grow back or overgrew.
Researchers now are trying to determine why the nerve cells grow back normally, abnormally or not at all, and whether the damaged nerve tissue disrupts mood, memory and other functions associated with serotonin.
Scientists also are trying to clarify serotonin's role in the brain and its possible involvement in some mental disorders such as depression and anxiety. MDMA users in Ricaurte's 1993 study were less hostile and impulsive than a control group of people who had a similar drug lifestyle but had not used MDMA.
MDMA, which is related to amphetamine and mescaline, was first synthesized in 1914 in drug company labs as a possible appetite suppressant. It did not appear as a recreational drug until the early 1980s and often is used at "raves," the large, all-night parties.
Other researchers were lead author Carl Fischer, George Hatzidimitriou, Jennifer Wlos and Jonathan Katz, Ph.D. The study was funded by a U.S. Public Health Service research grant from the National Institute on Drug Abuse.