Action of Light on the Neuroendocrine Axis
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Photoentrainment of the circadian clock located in the hypothalamic suprachiasmatic nucleus (SCN) is fundamental for the stable regulation of neuroendocrine function underlying physiological functions such as metabolism, sleep, immune responses, and reproduction. Masking by light directly suppresses melatonin secretion independent of the circadian system, with impact on several neuroendocrine axes. This chapter describes recent findings in anatomy and physiology on how light mediates its effects on SCN-regulated timing of the neuroendocrine system, including the hypothalamic-pituitary-adrenal (HPA) axis, the hypothalamic-pituitary-thyroid (HPT) axis, the hypothalamic-pituitary-gonadal (HPG) axis, and melatonin and arginine-vasopressin (AVP) secretion. In modern societies, artificial light at night (ALAN) seems to affect circadian and neuroendocrine systems, and should be considered in the understanding the health problems of the industrialized human population.
KeywordsPhotoreceptors Neurotransmitters Neuroendocrine Circadian Seasonal
This work was supported by the Danish Biotechnology Center for Cellular Communication.
- Engelmann M, Landgraf R (1997) Intracerebral release of vasopressin and oxytocin: new aspects of the old concept of neurosecretion. In: Korf H-W, Usadel K-H (eds) Neuroendocrinology Retrospect and perspectives. Springer, Berlin, pp 87–97Google Scholar
- Hannibal J, Hsiung HM, Fahrenkrug J (2011) Temporal phasing of locomotor activity, heart rate rhythmicity, and core body temperature is disrupted in VIP receptor 2-deficient mice. Am J Physiol Regul Integr Comp Physiol 300(3):R519–R530. https://doi.org/10.1152/ajpregu.00599.2010CrossRefPubMedGoogle Scholar
- Klein DC, Moore RY, Reppert SM (1991) Suprachiasmatic nucleus. The mind’s clock. Oxford University Press, New YorkGoogle Scholar
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- Do MT, Yau KW (2010) Intrinsically photosensitive retinal ganglion cells. Physiol Rev 90(4):1547–1581. A small population of retinal ganglion cells in the mammalian eye that express a unique visual pigment called melanopsin. This review describes the anatomy and physiology of this remarkable system.Google Scholar
- Golombek DA, Rosenstein RE (2010) Physiology of circadian entrainment. Physiol Rev 90(3):1063–1102. This paper reviews the anatomy and physiology of the circadian timing system in mammals.Google Scholar
- Kalsbeek A, Palm IF, La Fleur SE, Scheer FA, Perreau-Lenz S, Ruiter M et al (2006) SCN outputs and the hypothalamic balance of life. J Biol Rhythms 21(6):458–469. This review considers the anatomical connections and neurotransmitters used by the SCN to control the daily rhythms in hormone release.Google Scholar