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Dr. Tancer is studying the interaction between dopamine and serotonin systems. |
It has been well-established in pre-clinical laboratory studies that the neurotransmitter dopamine plays a significant role in the actions of drugs that contribute to their abuse. This neurotransmitter has been shown to be especially important for the abuse of psychomotor stimulants, such as cocaine and methamphetamine. However, similar studies in humans using medications that modulate the effects of dopaminergic neurotransmitter system have not been as convincing, according to Manuel Tancer, MD, associate professor in psychiatry and behavioral neurosciences. Instead, Dr. Tancer believes there is evidence that other neurotransmitter systems are also involved.
To study the role of other neurotransmitters in the abuse liability of psychomotor stimulants in humans, Dr. Tancer recently received a five-year $750,000 grant from the National Institute on Drug Abuse to study the interaction between dopamine and serotonin systems. "Animal studies have just begun to show that serotonin systems may also mediate some of the effects of psychomotor stimulants by influencing dopamine systems," said Dr. Tancer. "This may explain why the human studies have yielded equivocal results."
For this work, Dr. Tancer and his research group will compare classic dopamine and serotonin drugs to drugs with mixed dopamine/serotonin properties on a variety of behavioral measures in humans that are known to be sensitive to drug effects related to abuse and dependence. Other studies will use agents that block one or the other neurotransmitter system to detrmine how the blockade alters dependence-related effects. "If we do show an interaction between systems, this may help us develop new medication strategies that modulate both systems and lead to greater treatment success," said Dr. Tancer.