New research on rodents suggests that immunization prior to stress exposure could lessen the effects of PTSD.

Scientists have known for quite some time that immune disorders and stress are related. Anti-inflammatory drugs used in clinical trials have shown to reduce depression symptoms. This evidence creates the basis for the study into how Post Traumatic Stress Disorder can be prevented or treated.

To test whether mice reacted differently before and after an injection of Mycobacterium vaccae, a common bacteria, researchers placed them in cages with much bigger, more aggressive animals. The mice who had received the injection reacted more proactively to the stress than the control group, while some mice in the control group developed inflamed colons and other markers of stress.

Another experiment played an abrasive sound aligned with an electric shock to mice who had been injected with M. Vaccae, and those who had not. Then, the shock was removed from the sound to eliminate the fear. When exposed to the sound, immunized mice became resistant to it much faster than the control group.

Mycobacterium vaccae has been used in many clinical trials, and experts believe this could make it easier to approve for a possible PTSD vaccine.

Cover image: Wikipedia