Opposite effects of estrogen receptor alpha and beta specific agonists on social learning of food preferences
In the social transmission of food preferences, learning from conspecifics allows individuals to bypass the risks associated with trial-and-error learning. Females in proestrus and diestrus show a longer preference for the demonstrated food than estrus and ovariectomized females. Estrogen receptors (ER) alpha and beta are both involved in various social behaviours, suggesting that they may be involved in social learning. This thesis investigates the effect of an ER[alpha] selective agonist (PPT) and an ER[beta] selective agonist (WAY-200070) on social learning in ovariectomized mice. PPT blocked social learning, while WAY-200070 produced a twofold prolonged preference for the demonstrated food. These results cannot be explained by non-specific effects on food intake or type of interaction with the demonstrator. The WAY-200070-induced prolonged food preference was similar to that seen in proestrus and diestrus mice. This suggests that the estrous cycle's effects on social learning may be due to action of estrogens on ER[beta].