Author(s)

Evgeny Bojko, Anastasiya Kaneva, Natalya Potolitsyna

.

The monthly investigations of military guards ((19.1 ? 0.9) years, n = 20) in northern European region (62?N lat.) that daily spent outdoors from 6 to 10 h were carried out during the year (from November to October). In examined subjects, the serum FT4 levels were high enough during all period of research espe-cially from April till October when the hormone levels exceeded norm. The concentration of serum FT3 was rather stable during the year and corresponded to the normal level. At the same time, the levels of total form of thyroid hormones (TT4 and TT3) displaced to lower limit of norm. Thus, staying outdoors of military guards in the North for all the year round is accompa-nied by activization of thyroid hormones use.

Thyroid Hormones; Human; Adaptation;North; Cold

Bojko, E. , Kaneva, A. and Potolitsyna, N. (2011) The annual cycle of the pituitary-thyroid axis activity in healthy men under prolonged cold air exposure. Journal of Biomedical Science and Engineering, 4, 462-471. doi: 10.4236/jbise.2011.46058.