Molecular cloning of medaka orexin and orexin receptor and decreased spontaneous movement in response to an orexin inhibitor

抄録

Orexin （hypocretin） is a neuropeptide secreted by hypothalamic neurons that is activated during motivating behaviors and active waking. Our knowledge of orexin is mainly limited to mammalian species, such as humans, mice, and rats. In the present study, we cloned orexin and its receptor from the medaka brain. Additionally, we analyzed the effect of an orexin inhibitor （SB-649868） on spontaneous behavior. The orexin inhibitor decreased spontaneous movement of the fish, suggesting the importance of the orexin system in spontaneous movement. Our results indicate that medaka might be a suitable animal model for neurological behavioral studies.