Ketamine-Induced Social Interaction Deficits

Experimental schedule was taken from (Ogundele and Lee, 2018 (link); Sultana and Lee, 2020 (link)). Mice were randomly allocated to the three treatment groups listed in Table 1 (n = 8 for each group, i.e., 24 animals in total). Ketamine (Ketamine hydrochloride, Biowet, Poland) was administered once a day for 5 days (i.p., 30 mg/kg, 5 μl/g). Five days after the last injection social interactions with a novel conspecific were assessed in the partition test (Figure 1A). Four hours before the test, animals received norbinaltorphimine (norbinaltorphimine dihydrochloride, 0347, Tocris, UK) injection (i.p., dissolved in saline, 10 mg/kg, 5 μl/g). Three days after the partition test, social interaction with an unfamiliar conspecific placed under an enclosure was measured in the open field. Norbinaltorphimine was reported to act for up to 2 weeks (Lalanne et al., 2017 (link)), thus a single injection is sufficient to achieve persistent effects during both behavioral tests, performed 3 days apart.