14 DAY TRIAL // A team of investigators based at the Vanderbilt University in the United States announces the discovery of cannabinoid receptors in the brains of lab mice. This discovery is very important because it may go a long way towards explaining why marijuana has such a calming effect on anxiety and panic attacks. The team now plans to see whether or not a similar system exists in humans as well.
Upon studying unsuspecting mice in the lab, researchers were able to identify a series of cannabinoid receptors in a section of the brain called the amygdala. In humans, this deep-seated portion of the brain plays a critical role in controlling our responses to fear and in regulating anxiety and the body's innate fight-or-flight response.
In the new study, the central region of the amygdala was found to be primed to receive cannabinoids. These chemicals are in the same family as tetrahydrocannabinol, or THC, the main active substance in marijuana. This research comes on the heels of other recent studies that look at the effects compounds called endocannabinoids have on pain suppression and relief in humans.
Endocannabinoids are cannabinoids that the human body produces naturally, most often following a traumatic event, or whenever pain relief is needed. All of these new findings put marijuana smokers' claims of feeling anxiety relief when using pot in a new light, PsychCentral reports.
The senior author of the study, Vanderbilt professor of psychiatry, molecular physiology, and biophysics Sachin Patel, MD, PhD, says that this investigation “could be highly important for understanding how cannabis exerts its behavioral effects.” This is a very important goal, since an increasing number of states in the US are considering legalizing pot for public consumption.
What studies have determined to date is that emotional or chronic stress can reduce the amount of endocannabinoids the body produces, leading to anxiety and panic attacks in all age groups. This is one area where marijuana-based – or at least cannabinoid-based – therapies could come in handy.
Recent studies have also determined that the endocannabinoid system produces its effects by acting on the neurotransmitter glutamate. By doing so, these compounds reduce the amount of excitatory signals passing through the brain, helping anxiety patients calm down faster.
The research team also included experts from the Hokkaido University in Sapporo, Japan, the Hungarian Academy of Sciences in Budapest, and the Indiana University in Bloomington. The first author of the research was graduate student Teniel Ramikie, also from Vanderbilt. Details of the study appear in the latest issue of the top scientific journal Neuron.
“We know where the receptors are, we know their function, we know how these neurons make their own cannabinoids. Now can we see how that system is affected by […] stress and chronic (marijuana) use? It might fundamentally change our understanding of cellular communication in the amygdala,” Patel concludes.