Circadian and circannual oscillations in thyroglobulin in the healthy adult male
Guagnano, M.T.; Angelucci, E.; Cervone, L.; Menduni, P.; Sensi, S.
Bollettino della Societa Italiana di Biologia Sperimentale 62(3): 315-320
1986
ISSN/ISBN: 0037-8771 PMID: 3718748 Document Number: 272149
Human thyroglobulin (h Tg) is nomally secreted by the thyroid gland together with hormonal products, of which represents the prohormone and its synthesis and secretion are influenced specifically by thyroid stimulating hormone (TSH). Many variables of the hypothalamus-pituitary-thyroid net-work were investigated in relationship to the seasonal variations in man. An enhanced thyroid activity was found in winter; herein we planned to carry out a study on the existence of the circadian and circannual rhythm of serum h Tg evaluating 4 healthy males aged from 25-28 years. All were on the same diet physical and sleep-wakefulness regimen before and during the study. Blood samples were taken every four hours for 28 hrs, every first day of February, April, June, August, October, December. Data were evaluated by chronogram and Cosinor test. The results display the presence of a circadian rhythm with acrophase (hr/min) at 15,49' and a circannual rhythm with acrophase (day/month) at 18 May.