Ketamine psychosis C57BL/6N

Male 12-week-old C57BL/6N mice (Charles River Laboratories, Germany) were used as focal animals. Ketamine hydrochloride was administered once a day for five days (i.p., 30 mg/kg, 5 µl/g). Five days after the last injection, social interactions were assessed in the partition test. Three days after the partition test, a social interaction test in the open field was performed. Partition test The test consisted of habituation and sociability tests, 5 minutes each. During habituation, the actor was introduced to an empty cage (50 ´ 12 ´ 24.5 cm height). The cage was divided into two compartments by a transparent, perforated plastic separator. The smaller compartment (1/4 of the cage) was designated to be the partner’s compartment during the second phase. After habituation, the actor was moved to a transport cage for a short time, during which a partner was placed in his compartment, and immediately afterwards, the actor was introduced to the other part of the cage. Open field test The test consisted of habituation and social interaction tests, 5 minutes each. For habituation, actors were introduced into an empty open field arena (55 ´ 37.5 ´ 20.5 cm height). Next, two wire cups (9 cm diameter, B-0197, Bionovo, Poland) were placed in the cage: one covering an unfamiliar conspecific and one empty (as a novel object).