Amphetamine abuse during adolescence permanently changes brain cells, according to new animal research. The study shows drug exposure during adolescence, but not young adulthood, altered electrical properties of brain cells in the cortex.
The findings were presented at Neuroscience 2010, the annual meeting of the Society for Neuroscience, held in San Diego.
Many children and teens with attention deficit hyperactivity disorder benefit from taking amphetamines, such as Adderall®, when closely supervised by parents and physicians. However, these drugs are also highly abused by healthy individuals, particularly adolescents between the ages of 12 and 17, a period when the brain continues to develop and mature.
To test the effects of amphetamine abuse on adult brain cell function, researchers at the University of Illinois, Urbana- Champaign repeatedly treated adolescent and young adult rats with the drug. When the rats reached adulthood, the researchers examined brain cells in the prefrontal cortex, a region important in memory, decision-making, and impulse control.
Brain cells from rats exposed to amphetamine abuse in adolescence, but not young adulthood, showed abnormal responses to electrical stimulation and insensitivity to the brain chemical dopamine. Because brain cells communicate using both electrical and chemical signals, these findings may indicate drug-induced disruptions in brain function.
Previous research showed deficits in working memory in adult rats exposed to amphetamines in adolescence. Our new findings reveal that this change in cognitive behavior may be due in part to long-lasting changes in the function of neurons in the prefrontal cortex, said the studys senior author, Joshua Gulley, PhD. We hypothesize that this is due to amphetamine disrupting the normal processes of brain development, he said.
Research was supported by the National Eye Institute.