Modulation of Brain Reward Circuitry by Leptin

TLDR

Leptin, a hormone secreted by fat cells, suppresses food intake and promotes weight loss. The study assessed leptin’s action on brain reward circuitry by measuring changes in the rewarding effect of lateral hypothalamic stimulation after leptin administration. Chronic food restriction enhanced rewarding stimulation at five fornix sites, while leptin infusion attenuated it; at neighboring sites the effect was insensitive to restriction but leptin enhanced it in most cases, suggesting leptin produces opposing changes in reward for feeding versus competing behaviors.

Abstract

Leptin, a hormone secreted by fat cells, suppresses food intake and promotes weight loss. To assess the action of this hormone on brain reward circuitry, changes in the rewarding effect of lateral hypothalamic stimulation were measured after leptin administration. At five stimulation sites near the fornix, the effectiveness of the rewarding electrical stimulation was enhanced by chronic food restriction and attenuated by intracerebroventricular infusion of leptin. In contrast, the rewarding effect of stimulating neighboring sites was insensitive to chronic food restriction and was enhanced by leptin in three of four cases. These opposing effects of leptin may mirror complementary changes in the rewarding effects of feeding and of competing behaviors.