THE ROLE OF GHRELIN IN CONTROL OF EMOTIONAL, EXPLORATIVE AND MOTOR BEHAVIOR IN EXPERIMENTAL POSTTRAUMATIC STRESS DISORDER

Relevance. Human survival in emergencies is often accompanied by the formation of post-traumatic stress disorder (PTSD) as a result of acute mental trauma.

Intention. To study behavioral signs of experimental posttraumatic stress disorder (PTSD) and effects of ghrelin and its antagonist in the experiments on rats exposed to an acute psychoemotional stress.

Methods. PTSD was modelled by placing a group of rats to a tiger python who seized and swallowed one of them, others experienced unescapable stress. Then ghrelin (20 µg in 20 µl) or its antagonist [D-Lys3]-GHRP-6 (10 µg in 20 µl) were administered intranasally daily for 7 days. On 7th day after stress and administration of drugs, the behavior of rats was studied using open field, elevated plus maze and intruder-resident tests.

Results and Discussion. Ghrelin antagonist [D-Lys3]-GHRP-6 demonstrated mainly anxiolytic effect (open field and intruder-resident tests) but increased behavior signs of python-induced stress in the elevated plus maze. At the same time, ghrelin did not alter PTSD signs (elevated plus maze) or exerted sedative (suppressive) action (open field and intruder-resident tests).

Conclusion. Therefore, the data support the involvement of ghrelin system in controlling motor and emotional behavior during PTSD development.

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