[The brain histamine H3 receptors: sleep-wake control and novel therapeutic targets for sleep disorders]

Histaminergic neurons are located exclusively in the posterior hypothalamus from where they project to virtually all brain areas and fulfill a major role in the maintenance of waking. H3-receptors are firstly autoreceptors damping the release and synthesis of histamine and the firing of histamine neurons. This action also extends to heteroreceptors on most other neurotransmitter systems, allowing a powerful control over multiple homeostatic functions. The particular properties and locations of H3-receptors provide quite favorable attributes to make this a most promising target for sleep-wake control and sleep disorders. This review summarizes the most recent data on the role of H3-receptor in physiological sleep-wake regulation and preclinical and clinical evidence supporting H3-receptor as brain target for therapy of sleep and vigilance disorders.