ABSTRACT
In the past 10 years, sleep science has developed remarkably owing to the development of various types of molecular biological techniques. For example, a sleep center in the ventrolateral preoptic area (VLPO) and an arousal center in the tuberomammillary nucleus (TMN) were identified by immunostaining the hypothalamus of sleeping and waking animals, respectively, for c-Fos-positive neurons.1-3 Hypocretin (orexin) was discovered as a neuropeptide involved in narcolepsy.4
