The central nervous system sites of known direct ghrelin action are indicated here, superimposed onto a photomicrograph of a whole mouse brain. They include several hypothalamic nuclei (ARH, PVH, VMH, and LH), the hippocampus, the amygdala, the VTA, and the dorsal vagal complex [including AP, NTS, and DMN]. Abbreviations: AP, area postrema; ARH, arcuate nucleus of the hypothalamus; DMN, dorsal motor nucleus of the vagus; LH, lateral hypothalamic area; NTS, nucleus of the solitary tract; PVH, paraventricular nucleus of the hypothalamus; VMH, ventromedial nucleus of the hypothalamus; VTA, ventral tegmental area.