Effects of isolation-rearing on voluntary consumption of ethanol, sucrose and saccharin solutions in Fawn Hooded and Wistar rats.

These experiments examined the hypothesis that isolation-rearing and strain influence hedonic mechanisms. In experiment 1, voluntary consumption of ethanol and water was monitored in the home cage of Fawn Hooded (FH) and Wistar rats. FH rats were found to consume more ethanol at low concentrations than Wistar rats, independent of rearing condition, and isolation-reared rats were found to consume more of high ethanol concentrations, independent of strain. In experiment 2, isolation-reared rats were found to consume more sucrose, independent of concentration, than socially reared rats. In experiment 3, Fawn Hooded rats were found to be more sensitive to low concentration solutions of saccharin, and to consume less of the high concentration solutions, while isolation-rearing was found to enhance consumption of high concentrations. Thus, hedonic processes are independently modulated by strain and rearing conditions, although the effects of isolation-rearing appear to be exacerbated in Fawn Hooded rats.