The endocannabinoid system plays a key role in stress, according to a study

According to a recent study, the way in which the body's endocannabinoid system responds to stress could open up a new avenue for cannabinoid-based treatment of psychiatric disorders.

Conducted on mice, the study found that a key emotional brain center, the amygdala, releases endogenous cannabinoid molecules (specific to the organism) in the event of stress, and that these molecules attenuate the stress alarm emitted by the hippocampus, a brain center for memory and emotion, by activating the same brain receptors as THC derived from cannabis plants.

However, the brain activity patterns and neural circuits regulated by these brain-derived cannabinoid molecules are not well known.

These results confirm the hypothesis that these endogenous cannabinoid molecules are the body's natural response to stress.

Exposure to stress increases the risk of developing or worsening psychiatric disorders, from generalized anxiety to major depression. post-traumatic stress disorder (PTSD).

For this study, scientists from the Northwestern Medicine used a new protein sensor capable of detecting the presence of these cannabinoid molecules at specific brain synapses in real time, to show that specific high-frequency patterns of amygdala activity can generate these molecules.

The sensor also showed that these molecules were released following different types of stress in mice.

When scientists removed the target of these cannabinoids, the cannabinoid receptor type 1 (CB1), this led to poorer stress coping and motivational deficits in the mice.

More specifically, when the target receptor for these endogenous cannabinoids is suppressed at hippocampal-amygdala synapses, mice take on more passive reactions and immobile in the face of stress, and less likely to drink sucrose-sweetened water after exposure to stress.

This latter finding could be linked to the anhedonia, or diminished pleasure, often experienced by patients suffering from stress-related disorders such as depression and post-traumatic stress disorder (PTSD).

The study's corresponding author, Dr. Sachi Patel, Chair of Psychiatry and Behavioral Sciences at the Northwestern University Feinberg School of Medicine and psychiatrist at Northwestern Medicine, said: «Understanding how the brain adapts to stress at the molecular, cellular and circuit levels could provide vital insights into how stress translates into mood and mood disorders. could reveal new therapeutic targets for the treatment of stress-related disorders...

According to Dr. Patel, the study could indicate that deficiencies in this endogenous cannabinoid signaling system in the brain could lead to greater susceptibility to the development of stress-related psychiatric disorders, including depression and post-traumatic stress, although this remains to be determined in humans.

The endocannabinoid system is one of the key signaling systems that has been identified as an important candidate for the development of drugs for stress-related psychiatric disorders.

Dr Patel continues: «Determining whether increased levels of endogenous cannabinoids can be used therapeutically potential for disorders is the next logical step in this and our previous work.

Clinical trials currently underway in this field could make it possible to answer this question in the near future.

The research was supported by grants from the National Institute of Mental Health and the National Institute on Alcohol Abuse and Alcoholism, Integrative Neuroscience Initiative on Alcoholism, all from the National Institutes of Health.