Post-traumatic stress disorder is difficult to diagnose, and some might be more vulnerable to it than others, so scientists have been investigating whether a blood test or biological marker can identify the mental illness.
Well, researchers think they may have found one in rats. In a recent study has been published in the Proceedings of the National Academy of Science, researchers took dozens of laboratory rats and induced stress by exposing them to used cat litter. The scent of the cat’s urine was the source of the rat’s stress since they assessed it as a threat. After seven days, researchers tested the rats for PTSD symptoms using a maze. If the rats recoiled in a closed section of a maze, rather than rely on their natural instinct to explore, they were deemed to be effected by the stressors.
Researchers then analyzed the rat’s gene expressions in blood and two parts of their brain. Rats who were displaying symptoms related to PTSD had a distinctive pattern of glucocorticoid receptors signaling.
The second phase of the experiment consisted of the rats being injected shortly after being exposed to the cat litter with corticosterone, a hormone that activates the glucocorticoid receptors. Researchers found that the rats showed fewer symptoms of PTSD versus the rats who did not receive the injections.
Dr. Dr. Nikolaos Daskalakis, a neuroendocrinologist at Mount Sinai Hospital in New York and lead researcher for the study, says that clinical trials are already moving forward to identify if glucocorticoid injections given to survivors of serious car accidents can help prevent PTSD.