The arcuate nucleus is a group of neurons in the mediobasal hypothalamus, lying alongside the third ventricle and the median eminence. The arcuate nucleus includes several important populations of neurons, including: neuroendocrine neurons, which release dopamine into the hypophysial portal blood; and centrally-projecting neurons and Others.
The centrally-projecting neurons in the arcuate nucleus release neuropeptide Y, which influence hunger. When these neurons are activated, they can produce remarkable increases in eating that result in obesity. If such is the case, these neurons may be regulated by glucose, insulin, and the hormone leptin.