E O Kutcher1, A Yu Egorov1, N A Chernikova2. 1. Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences; St. Petersburg State University, St. Petersburg. 2. Sechenov Institute of Evolutionary Physiology and Biochemistry of the Russian Academy of Sciences.
Abstract
OBJECTIVE: To study the formation of alcohol preference in rats subjected to early social isolation, a possible model of schizophrenia. MATERIAL AND METHODS: The study was carried out on 45 Wistar male rats, aged 21--24 days. The experimental animals were dropped from the parental cells in the individual cells for 35 days, control rats were kept in standard conditions (5 animals per cage). Allanimals were subjected to forced alcohol drinking for three and ahalf months according to the following scheme: access to the15% ethanol solution (Monday, Wednesday, Friday), drinking deprivation (Tuesday, Thursday), free access to the water (Saturday, Sunday). Alcohol preference was evaluated in the «two-bottle» test, behavior characteristics -- in the «open field» and the «behavioral despair» tests. RESULTS AND CONCLUSION: Rats subjected to isolation significantly more of ten preferred alcohol in the «two-bottle» test after 0.5, 2 and 3 months of forced alcohol drinking. After the end of isolation and before forced alcohol drin-king, the experimental rats showed greater locomotor activity in the «open field» test. According to the exploratory activity and emotionality, the rats in both groups had no significant differences. The rats subjected to isolation, were significantly more sensitive to the sound stimulus and lingered ongerin the start area in the «open field». Thus, the combination of early social isolation and forced alcohol drinking leads to greater alcohol preference in experimental animals. Significant differences in alcohol preference were observed after the start of forced alcohol drinking while immediately after isolation the rats of both groups had no differences in their relation to alcohol. After 3.5 months of forced alcohol drinking, the isolated rats demonstrated decreased behavioral despair in the same test.
OBJECTIVE: To study the formation of alcohol preference in rats subjected to early social isolation, a possible model of schizophrenia. MATERIAL AND METHODS: The study was carried out on 45 Wistar male rats, aged 21--24 days. The experimental animals were dropped from the parental cells in the individual cells for 35 days, control rats were kept in standard conditions (5 animals per cage). Allanimals were subjected to forced alcohol drinking for three and ahalf months according to the following scheme: access to the15% ethanol solution (Monday, Wednesday, Friday), drinking deprivation (Tuesday, Thursday), free access to the water (Saturday, Sunday). Alcohol preference was evaluated in the «two-bottle» test, behavior characteristics -- in the «open field» and the «behavioral despair» tests. RESULTS AND CONCLUSION:Rats subjected to isolation significantly more of ten preferred alcohol in the «two-bottle» test after 0.5, 2 and 3 months of forced alcohol drinking. After the end of isolation and before forced alcohol drin-king, the experimental rats showed greater locomotor activity in the «open field» test. According to the exploratory activity and emotionality, the rats in both groups had no significant differences. The rats subjected to isolation, were significantly more sensitive to the sound stimulus and lingered ongerin the start area in the «open field». Thus, the combination of early social isolation and forced alcohol drinking leads to greater alcohol preference in experimental animals. Significant differences in alcohol preference were observed after the start of forced alcohol drinking while immediately after isolation the rats of both groups had no differences in their relation to alcohol. After 3.5 months of forced alcohol drinking, the isolated rats demonstrated decreased behavioral despair in the same test.