Abstract
<jats:p> Orexin A and orexin B are hypothalamic peptides that act on their targets via two G protein-coupled receptors (OX<jats:sub>1</jats:sub> and OX<jats:sub>2</jats:sub> receptors). In the central nervous system, the cell bodies producing orexins are localized in a narrow region within the lateral hypothalamus and project mainly to regions involved in feeding, sleep, and autonomic functions. Via putative pre- and postsynaptic effects, orexins increase synaptic activity in these regions. In isolated neurons and cells expressing recombinant receptors orexins cause Ca<jats:sup>2+</jats:sup> elevation, which is mainly dependent on influx. The activity of orexinergic cells appears to be controlled by feeding- and sleep-related signals via a variety of neurotransmitters/hormones from the brain and other tissues. Orexins and orexin receptors are also found outside the central nervous system, particularly in organs involved in feeding and energy metabolism, e.g., gastrointestinal tract, pancreas, and adrenal gland. In the present review we focus on the physiological properties of the cells that secrete or respond to orexins. </jats:p>
Original language | English |
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Pages (from-to) | C1567-C1591 |
Number of pages | 0 |
Journal | American Journal of Physiology-Cell Physiology |
Volume | 283 |
Issue number | 6 |
DOIs | |
Publication status | Published - 1 Dec 2002 |