Neuroendocrine Role of the Orexins (Hypocretins)

  • Shahrad Taheri
Part of the Contemporary Clinical Neuroscience book series (CCNE)


Although the orexin (hypocretin) neuron cell bodies are exclusively located in the lateral perifornical hypothalamus (the classical “feeding center”), they send projections throughout the neuraxis (1,2). This suggests that orexin neuropeptides and their receptors have functions beyond their originally observed effects on food intake and their currently accepted pivotal role in the regulation of sleep and wakefulness (3, 4, 5, 6). In particular, orexin fibers have been observed to innervate several brain, and specifically hypothalamic, regions that are intimately involved in the regulation of pituitary hormone secretion. Therefore, a link between the orexins and pituitary hormone secretion appeared highly likely from the outset. This view was underscored by the observed role of orexins in sleep regulation, since the secretion of some hormones is closely linked to circadian rhythms (e.g., corticotrophin, [AC TH]) and sleep (e.g., growth hormone).


Prolactin Secretion Pituitary Hormone Secretion Hypothalamic Explants Orexin Fiber Neuroendocrine Role 
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Copyright information

© Humana Press Inc., Totowa, NJ 2006

Authors and Affiliations

  • Shahrad Taheri
    • 1
  1. 1.Henry Wellcome Laboratories for Integrative Neuroscience and EndocrinologyUniversity of BristolUK

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