Orexin-induced feeding requires NMDA receptor activation in the perifornical region of the lateral hypothalamus.

Food intake is stimulated following administration of orexin-A into the perifornical region of the lateral hypothalamus (LH/PFA). Orexin neurons originating in the LH/PFA interact with a number of hypothalamic systems known to influence food intake, including glutamatergic neurons. Glutamatergic systems in the LH/PFA were demonstrated to initiate feeding through N-methyl-d-aspartic acid (NMDA) receptors.

Estradiol-induced conditioned place preference may require actions at estrogen receptors in the nucleus accumbens.

Intrinsic rewarding effects of estradiol (E(2)) may underlie some of the sex differences that emerge postpuberty for the prevalence of drug use and behavioral responses to drugs, but the effects and mechanisms of E(2) for reward have not been well characterized. Conditioned place preference (CPP), as measured by the time spent on the nonpreferred/drug-associated side of the chamber, was utilized as a functional assay to investigate the effects and mechanisms of E(2) in the nucleus accumbens for reward. To determine whether intracellular estrogen receptors (ERs) are important for E(2)-induced CPP, rats were administered E(2) (10 microg; subcutaneously (s.