Pages 161-164 in J. Lepp�¤luoto, ed. Circumpolar Health 2003. Proceedings of the 12th International Congress on Circumpolar Health, Nuuk, Greenland, September 10-14, 2003. International Journal of Circumpolar Health. 2004;63(Suppl.2)
Department of Physiology, University of Oulu, Finland. juhani.leppaluoto@oulu.fi
Source
Pages 161-164 in J. Lepp�¤luoto, ed. Circumpolar Health 2003. Proceedings of the 12th International Congress on Circumpolar Health, Nuuk, Greenland, September 10-14, 2003. International Journal of Circumpolar Health. 2004;63(Suppl.2)
OBJECTIVES: We set out to find out in which way seasonal changes of environmental luminosity could affect melatonin secretion in humans. STUDY DESIGN: For an entire year we collected every two months nocturnal urine samples from 20 male outdoor workers who lived and worked in an area of the circumpolar region from which exact data solar irradiance and temperature were available. METHODS: Melatonin secretion rates were assessed with our melatonin-specific radioimmunoassay. RESULTS: Melatonin secretion was twice as high in December as in April, 0.88 +/- 16 nmol/12 h (mean +/- SE) vs. 0.43 +/- 9 nmol/12 h, p