Neuropeptides that play a significant role in the regulation of food intake and sleep-wakefulness, possibly by coordinating the complex behavioral and physiologic responses of these complementary homeostatic functions. A broader role in the homeostatic regulation of energy metabolism, autonomic function, hormonal balance and the regulation of body fluids, is also suggested.
Binds to orexin receptors HCRTR1/OX1R and HCRTR2/OX2R with a high affinity (By similarity). Stimulates food intake (By similarity). Modulates pituitary luteinizing hormone secretion in an ovarian steroid-dependent manner (By similarity).
Binds to orexin receptor HCRTR2/OX2R only (By similarity). Stimulates food intake (By similarity). Modulates pituitary luteinizing hormone secretion in an ovarian steroid-dependent manner (By similarity).
Subcellular locations: Rough endoplasmic reticulum, Cytoplasmic vesicle, Synapse
Associated with perikaryal rough endoplasmic reticulum as well as cytoplasmic large granular vesicles at synapses.
Abundantly expressed in subthalamic nucleus but undetectable in other brain regions tested (hypothalamus was not tested) and in heart, placenta, lung, liver, skeletal muscle, kidney and pancreas.