Cocaine: Serotonin vs. Dopamine

Last Updated: Sep 20th 2019

Reviewed by Brittany Polansky, MSW, LCSW

Most people are very aware of long term physical and psychological damages that ravage a person suffering from substance use disorder with cocaine as their preferred drug; heart and vascular issues, nasal problems that include collapsed septum in severe cases, unstable mood and sometimes violent behaviors are well known. The mechanics of the addiction side of the equations are only just now being uncovered by research, but still have many hurdles to fully explain how the drug affects the behavior of people who become addicted to it.

Recently, the Florida Atlantic University’s Brain Institute in association with Vanderbilt University and the Research Triangle Institute, ran a study with mice standing in as an analogue for humans that suggests serotonin might be playing a role in addiction to cocaine in addition to what has already been identified to be contributing factors involving dopamine. The neurobiologists conducting the study deployed the use of genetically engineered mice which were given a a serotonin inhibition trait. This inhibitor blocked the receptors and transmitters of serotonin in their brains.

When these mice were given cocaine, the results, when compared to the mice without this specially engineered trait, did not behave as if they were experiencing the ‘high’. Normally, when cocaine is administered to normal mice, they tend to become hyperactive and run around haphazardly a lot more. However, the mice which had their serotonin levels minimized did not exhibit this behavior in comparison.

The catch to the study, though, shows that despite not exhibiting the immediate ‘high’ effects of cocaine, they were still shown to want to obtain more of the drug with very little difference in this behavior between the engineered mice and the unaltered control mice. It was believed, until this experiment showed otherwise, that dopamine release itself was highly responsible for the high that people experience on cocaine. The experiment, which is the beginning of a new direction for researchers to follow, may be highly important in developing medication assisted treatments (MAT) in combating cocaine addiction, similar to drugs like naloxone which has been shown to be effective as a medication to treat opioid addiction. The resulting drug from this line of research is not likely to have the same approach to the neurobiology due to the findings of research thus far.

The gene in the engineered mice that was altered is also one that is known to be in part responsible for patients diagnosed with ADHD (attention deficit hyperactivity disorder) and bipolar disorder. According to the study’s lead author, Randy D. Blakely, Ph.D., the research was primarily interested in ADHD research but, “we think there may be some very important lessons here that could help those dealing with substance use disorder.”

Our Broward County drug rehab center in Pompano is equipped to handle not only cocaine use disorders but also handle withdrawal from oxycodone and other drugs. Call First Step Behavioral Health for more information at (866) 971-5531.

Reviewed for Medical & Clinical Accuracy by Brittany Polansky, MSW, LCSW

Brittany has been working in behavioral health since 2012 and is the Assistant Clinical Director at our facility. She is an LCSW and holds a master’s degree in social work. She has great experience with chemical dependency and co-occurring mental health diagnoses as well as various therapeutic techniques. Brittany is passionate about treating all clients with dignity and respect, and providing a safe environment where clients can begin their healing journey in recovery.