Tetrahydrocannabinol is the chemical present in marijuana responsible for it’s psychological effects. Discovered in 1964, it was first isolated and synthesized in Israel by a scientist called Dr. Raphael Mechoulam. He actually did this illegally by obtaining cannabis from his friends in the police force after his curiosity got the better of him. The active compounds in cocaine and in heroin had been isolated but not in marijuana; the reason for his interest. This ‘high’ that is experienced can be seen from two viewpoints: those who seek it more often than not describe it positively and those on the outside or experienced negative effects see it as life changing and often ‘ruining’.
In this article i will be focusing on the latest discovery at University of Western Ontario, in which researchers there have identified a mechanism, located in the prefrontal cortex, that is responsible for the negative affects of THC such as mental health, of marijuana use, specifically in adolescents. Consequently they were also able to identify a mechanism to reverse the risks. According to the study THC modulates the activity of a neurotransmitter called GABA (which has previous links of clinical association with schizophrenia.) It works as an inhibitory neurotransmitter regulating excitation activity: therefore if you have less GABA your neuronal systems become more hyperactive. Hyperactivity of the brain is consistent with schizophrenia traits such as hallucinations. The study showed that exposure to THC in adolescence not only reduced the amount of GABA but also caused it to be out of sync with other areas of the brain resulting in a hyperactive state in the brains dopamine system during adulthood. The researchers used rats and tested drugs designed to increase the levels of GABA being produced: the rats had reduced and in some cases eliminated schizophrenia symptoms.
There is an ongoing battle on whether marijuna should be legalised or not in many countries. Whether for medicinal or recreational use, the question remains. Research such as that at the University of Western Ontario is a breakthrough for those who thrive on positive effects, and those who argue against it due to the negative side effects because it means the negatives can be blocked by taking medication to increase GABA levels.
References: Justine Renard, Hanna J. Szkudlarek, Cecilia P. Kramar, Christina E. L. Jobson, Kyra Moura, Walter J. Rushlow, Steven R. Laviolette. Adolescent THC Exposure Causes Enduring Prefrontal Cortical Disruption of GABAergic Inhibition and Dysregulation of Sub-Cortical Dopamine Function. Scientific Reports, 2017; 7 (1) DOI: 10.1038/s41598-017-11645-8