PET Study Finds Lower CB1 Receptor Availability After Childhood Trauma

Researchers used positron emission tomography with the CB1R-specific radiotracer [11C]OMAR to compare receptor availability in 22 adults with a history of childhood trauma and 22 age- and sex-matched healthy controls without reported childhood trauma. Linear models assessed global availability and measurements in the amygdala, hippocampus and frontal cortex.

CB1R availability was lower in the trauma group globally by 11.36% (p=0.04), and in the amygdala by 13.70% (p=0.01) and hippocampus by 14.50% (p=0.01). The difference in the frontal cortex was not statistically significant (8.08% lower; p=0.14). The researchers reported no effects associated with diagnoses of post-traumatic stress disorder or major depressive disorder, nicotine dependence, or antidepressant use.

The findings provide preliminary evidence of an association between childhood trauma and lower CB1R availability in some brain regions. The small sample and observational design limit conclusions about causation or clinical significance. The authors call for replication and further study of how trauma characteristics relate to the endocannabinoid system.