Specific modulation of social memory in rats by cholinomimetic and nootropic drugs, by benzodiazepine inverse agonists, but not by psychostimulants

Abstract

The recognition of an unfamiliar juvenile rat by an adult rat has been shown to imply short-term memory processes. In this study the effect of various psychotropic drugs on this investigatory behaviour was examined. The procedure was as follows: an unfamiliar juvenile rat was placed in the home cage of an adult rat for 5 min. The time spent by the adult rat in investigating the juvenile was recorded. The adult rat was then immediately treated with vehicle or test compounds, and was again exposed for 5 min to the same juvenile 2 h later. At this time point vehicle-treated rats no longer recognized the juvenile rat, i.e. the time of investigation was similar to that observed during the first presentation. Arecoline (1 and 3 mg/kg IP), physostigmine (0.05 and 0.1 mg/kg SC), RS86 (0.5 mg/IP) and nicotine (0.125 and 0.5 mg/kg IP) reduced in a dose-dependent fashion the time spent in investigating the juvenile during the second exposure. This result cannot be attributed to nonspecific effects, since it was not observed when a different juvenile was used for the second exposure. The effect of arecoline was reversed by scopolamine, but not by methylscopolamine. Aniracetam reduced investigatory behaviour at the dose of 50 mg/kg IP. FG 7142 (5 mg/kg IP) and beta-CCM (0.4 mg/kg IP) were also active and their effect was reversed by Ro 15-1788. DL-Amphetamine (0.5 and 1 mg/kg IP), nomifensine (1.25-10 mg/kg IP) and strychnine (0.25 and 0.5 mg/kg IP) were ineffective or reduced this behaviour unspecifically.(ABSTRACT TRUNCATED AT 250 WORDS)

Short-term social memory in the laboratory rat: its susceptibility to disturbance

“…This emphasises the importance of introducing a novel juvenile as a control to distinguish between specific and non-specific effects of treatment (e.g. Perio et al, 1989;Gheusi et al, 1994b). The results of experiment one indicate that the implementation of some elements of common husbandry/experimental procedures appears to be sufficient to disrupt the short-term social memory of an adult laboratory rat, although we are as yet unable to completely rule out the possible effects of these environmental stimuli on non-specific states of arousal or motivation.…”

“…Studies have indicated that it is unlikely, however, that odour deposition, either by the adults on the juveniles, or by the juveniles in the home cages of the adults, influences the outcome of the social recognition test (e.g. Sawyer et al, 1984;Perio et al, 1989).…”

“…The same technique has been used to distinguish between non-specific and specific effects of drug treatments on social memory (e.g. Perio et al, 1989;Gheusi et al, 1994b). In this experiment, four treatments were used (see Table 2).…”

“…Perio et al, 1989), can fail to uncover differences in the absolute size of response. The data were analysed initially using a GLM for repeated measures, with treatment (1-5) and pre-experimental training experience (5 or 15min) as factors.…”

Prefrontocortical Dopamine Loss in Rats Delays Long-Term Extinction of Contextual Conditioned Fear, and Reduces Social Interaction Without Affecting Short-Term Social Interaction Memory

“…Regarding social interaction memory, the recognition of a juvenile was used (Dantzer et al, 1987). Short-term memory, as measured through this test, is disrupted after lesions of the septohippocampal pathway and is very sensitive to cholinergic drugs (Pério et al, 1989).…”