An area of the brain stem thought to be responsible among other things for stimulating reactions necessary for waking and arousing from sleep. It is also present as a collection of neurons in the hypothalamus, where it plays an important role in the development of the reproductive system as it releases pulses of the gonadotropin releasing hormone into the pituitary gland. The arcuate nucleus is one of the places in the body that produces the hormone ghrelin (the main place being the stomach). Here it stimulates the secretion of the growth hormone from the anterior pituitary gland, as well promoting adiposity (fat production) and appetite.
See Brain stem, Gonadotropin releasing hormone (GnRH), Growth hormone (or somatotropin), Hippocampus, Hormones, Hypothalamus, Pituitary gland, Sudden infant death syndrome (SIDS, crib or cot death)