Researchers today reported the first evidence that a mother's use of MDMA (ecstasy) during pregnancy may result in specific types of long-term learning and memory impairments in her offspring.
The research, published in the May 1, 2001, issue of the Journal of Neuroscience, was conducted by scientists from Children's Hospital Research Foundation and the University of Cincinnati College of Medicine. The researchers administered MDMA to two groups of newborn rats. One group received ecstasy twice a day for 10 days after birth (analogous to early third-trimester brain development in humans); the other group received ecstasy twice a day during days 11 through 20 (analogous to late human third-trimester brain development). To determine the effects of ecstasy on cognitive abilities, a series of maze and swimming tests were conducted on the rats when they reached an average age of 60 days. While no cognitive changes were noted in the rats given ecstasy at an earlier age, memory and learning deficiencies were noted in the group exposed to ecstasy during days 11-20. The ecstasy-induced disruption in both sequential and spatial reference memory-based learning was long-term and was still apparent after this group reached adulthood.
"This study adds to the evidence that ecstasy is a dangerous drug. Unfortunately, its popularity remains high, in part because some individuals still perceive that taking ecstasy is safe. As its use continues, increases in the number of users who are pregnant will inevitable occur. This study indicates that users may be damaging not only their own cognitive abilities but those of their children as well," says NIDA Director Dr. Alan I. Leshner.
The timing of ecstasy exposure during brain development may be critical as evidenced by cognitive changes in the 11-20 day old group. "The differences between the responses in newborn rats after MDMA administration most likely occurs because of the stage of maturation of the central nervous system at the time of exposure to MDMA," explains Dr. Vorhees, lead investigator.
He further explains that in adult animals, ecstasy exerts its effects by significantly decreasing serotonin levels and the number of re-uptake sites in the brain. However, in this study, only small changes in serotonin levels were noted in the brains of the newborn rats receiving ecstasy suggesting that developmental exposure to ecstasy may induce cognitive deficits in the fetus through different mechanisms than those of adults.
"These findings raise new concerns about ecstasy when exposure occurs during brain development in the human fetus," Dr. Vorhees concludes.
Note to reporters: The full text of this article appears in the May 2001 issue of Journal of Neuroscience (2001, 21, 3228-3235) and is available on the its Web site at http://www.sfn.org/.