Anxiolytic-like profile in Wistar, but not Sprague?Dawley rats in the social interaction test

Abstract

Different rat strains as well as differing test conditions have a major impact on the outcome of this animal test for anxiety.

Neurotransmitter and Behaviour: Serotonin and Anxiety

“…Increased illumination prevented the food intake entirely, while a reduction of light intensity increased the proportion of rats that fed in the aversive open field . These findings are consistent with other studies of rat behaviour in an open, aversive environment, showing that rats in a dimly lit open field had more social interactions than in a brightly lit open field (File and Hyde 1978;Rex et al 2004). We were able to show in this simple animal test not only the known anxiolytic effects of GABA agonists, such as diazepam and the -carboline abecarnil (Rex, Stephens et al 1996), but also the dose-related anxiety-reducing effects of 5-HT1A agonists, 5-HT2A antagonists and 5-HT3A antagonists.…”

“…Here, the change of behaviour of the more anxious Wistar rats was more pronounced. Diazepam increased social contacts only in the more anxious Wistar rats (Rex, Voigt et al 2004). The well-known anxiogenic mCPP decreased the number and duration of mutual contacts in both rat strains (Rex, Voigt et al 2004).…”

“…We found that the duration of individual housing before the test and the associated social deprivation, had a significant influence on the duration and frequency of social contacts. Without a previous isolation we observed little interest in the other animal (Rex, Voigt et al 2004). Reduction of the aversive nature of the test arena by lower illumination or by a previous habituation to the test arena led to increased social interaction and confirmed the results of (File and Hyde 1978).…”

“…Trullas and Skolnick 1993;Rex, Sondern et al 1996). During the validation of the social interaction test, we observed that anxious Wistar rats and less anxious Sprague Dawley rats differed in the severity of behavioural changes after modifications of the test (Rex, Voigt et al 2004). It was not known to what extend these behavioural differences were genetic determined or caused by environmental conditions during breeding and animal keeping.…”

Role of Social Encounter-Induced Activation of Prefrontal Serotonergic Systems in the Abnormal Behaviors of Isolation-Reared Mice

“…Previous studies have shown that prefrontal DA levels are higher during or after an aggressive encounter in both attacking and defending rats (Anstrom et al, 2009;Tidey and Miczek, 1996;van Erp and Miczek, 2000). Furthermore, exposure to tests of 'anxiety', such as the social interaction test, causes an increase in hippocampal 5-HT release in rats from the more anxious Wistar strain, but not in rats from the less anxious SpragueDawley strain (Rex et al, 2004). These studies suggest that neurochemical changes are involved in encounter-induced behaviors, although these neurochemical changes may be induced by both psychological and physical stress.…”