"...people who use (it) unwittingly put themselves at risk"
The common street drug "ecstasy" causes brain damage in people, according to a new Johns Hopkins study. In a report in The Lancet released this week, Hopkins scientists show that the drug -- known chemically as MDMA -- damages specific nerves in the brain that release serotonin, the nerve transmitter thought to play a role in regulating mood, memory, pain perception, sleep, appetite and sexual activity.
"We had long suspected MDMA was dangerous, based on our earlier studies in primates that showed nerve damage at doses similar to those taken by recreational drug users," says neurologist George Ricaurte, M.D., Ph.D., who led the research team. Additional studies by the team examined drug users' spinal fluid for levels of a serotonin by product; reduced amounts strongly suggested brain damage in humans.
"But this is the first time we've been able to examine the actual serotonin-producing nerve cells directly in the brain," Ricaurte says. Using a nerve-specific technique that took more than five years to develop, the scientists took PET scans of 14 men and women who reported heavy use of ecstasy. With a radio-labeled probe, the team targeted molecules -- serotonin transporters -- that normally reabsorb serotonin into nerve cells after it has done its job.
Like certain antidepressants, MDMA also attaches to serotonin transporters. The transporters lie embedded in the membranes of nerve cells, at the tips of fingerlike extensions called axons.
In the study, the PET scans showed MDMA users had far fewer serotonin
transporters than controls who didn't use the drug. Also, the greater the use
of MDMA -- some of the subjects had used it 200 or more times -- the greater the
loss. "These losses are significant, and, along with our early studies in
animals, suggest that nerve cells are damaged," says Ricaurte. Whether or not
the cells a
Contact: Marjorie Centofanti
Johns Hopkins Medical Institutions