The SIT was identical for both adolescent and adult mice. Twenty-four hours after the last session of AcSD, C57BL/6J adolescent or adult mice were assessed in the SIT to measure their approach and/or avoidance behavior toward a social target (Krishnan et al., 2007; Golden et al., 2011). Briefly, the SIT consisted of two sessions in which defeated and control mice were allowed to explore a squared-arena (42 × 42 cm) for a period of 2.5 min each session. In the first session, an empty wire mesh enclosure was located against one of the walls of the arena to determine baseline exploration. In the second session, an unfamiliar CD-1 aggressor was placed inside the wire mesh enclosure. The area that surrounded the enclosure was designated as the social interaction zone (14 × 9 cm), and the corners of the wall opposite to the enclosure were designated as corners (9 × 9 cm) and represented the farthest point from the social interaction zone. The time spent (in seconds) in the interaction zone and the corners was estimated during both sessions of the test. Animals that did not explore the arena during the first session (i.e., spent 0 s in any of the designated areas) were excluded from all analyses (2/159 adolescent mice). The social interaction ratio was calculated as the time spent in the interaction zone with the CD-1 aggressor present divided by the time spent in the interaction zone with the CD-1 aggressor absent. Defeated mice with a ratio <1.00 were classified as susceptible and a ratio ≥1.00 were classified as resilient. To ensure that high social interaction ratios reflected actual interest in the social target, resilient mice were also required to spend at least 60 s inside the interaction zone or were excluded from all analyses (5/159 adolescent and 2/111 adult mice). Mice with outlier interaction ratio scores were also excluded (4/159 adolescent and 2/111 adults). All SIT was performed under red light conditions between 11 A.M. and 4 P.M. and mice were tested in a counterbalanced order. Animal behavior was recorded with an overhead video camera for offline analysis using the software TopScanTM 2.0 (Clever Systems Inc.).

Note: The content above has been extracted from a research article, so it may not display correctly.

Please log in to submit your questions online.
Your question will be posted on the Bio-101 website. We will send your questions to the authors of this protocol and Bio-protocol community members who are experienced with this method. you will be informed using the email address associated with your Bio-protocol account.

We use cookies on this site to enhance your user experience. By using our website, you are agreeing to allow the storage of cookies on your computer.