Age effects on the social interaction test in early adulthood male rats

Abstract

The effects of age on active and passive social interaction were studied in Wistar rats using the social interaction test (S.I.T.). Individual behaviors such as ambulation, rearing, and defecation were also studied. Despite the widespread use of the S.I.T. in anxiety research, the effects of age on the S.I.T have not been studied thoroughly. Male Wistar rats of 75, 135, and 180 days old were used. Our results showed age effects on active social contact, passive social contact, ambulation, rearing, and defecation. At 135 days old, animals presented the lowest scores on active social behavior and the highest scores on defecation. Moreover, exploratory behavior measured by ambulation and rearing decreased with age. These results suggest that age could be a relevant variable in the social interaction test. Depression and Anxiety 12:226–231, 2000. © 2000 Wiley‐Liss, Inc.

Behavioral, neuromorphological, and neurobiochemical effects induced by omega-3 fatty acids following basal forebrain cholinergic depletion in aged mice

“…The anxiolytic pattern of our cholinergically depleted aged mice is also consistent with the increased exploration of open spaces in the EPM and reduced hiding in the MBT observed in mice with temporary and reversible inhibition of cholinergic neurons in the medial septum [67]. As for social interaction, it was scarce in our aged mice, as expected at late stage of life in rodents [65,76,119], and it was unaffected by the cholinergic lesion possibly due to a floor effect and/or to the sparing of striatal circuits linked to the rewarding properties of affiliative behaviors [54,120,121]. Regarding depressive-like responses, to our knowledge, this is the first study evaluating the performance of cholinergically depleted aged mice by using a two-session PT.…”

“…The first limitation of the present study may be the lack of young groups of mice lesioned and treated as the aged ones to also evaluate the age effect. For example, in the SIT, we found no significant effects of lesion or diet, but we can only hypothesize a floor effect linked to an agerelated decrease in social interest based on previous studies in rodents [65,76,119]. It should be pointed out, however, that i.c.v.…”

“…The social interactions test (SIT) is used to investigate social behaviors, which are known to decrease with age in rodents [65,76]. Moreover, a selective cholinergic depletion of neocortex is reported to cause a significant decrease in the duration of active social interaction with an unfamiliar male in adult rats [77].…”

Neuroprotective Role of Dietary Supplementation with Omega-3 Fatty Acids in the Presence of Basal Forebrain Cholinergic Neurons Degeneration in Aged Mice

“…The SI test is used to investigate social behaviors, which are known to decrease with age in rodents [66,74].…”