A radioimmunoassay study and comparison of seasonal variation in plasma triiodothyronine and thyroxine concentrations in normal healthy persons

Postmes, Th. J.; Hout, J.C. Van; Saat, G.; Willems, Paul; Coenegracht, J.M.

doi:10.1016/0009-8981(74)90366-0

Cited by 17 publications

(7 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In view of our observations it seems plausible to ascribe this finding to temperature induced changes in thyroid function, during pregnancv. The data from our study disagree with recent findings of Postmes et al (20) in Dutch males and females and with the data of Rastagi and Sahwney (15) in Indian males, both of which groups failed to demonstrate a seasonal variation in circulating serum T3 and T4 levels. The latter authors however observed a significantly higher urinary T3 and T4 excretion during the coldest Indian months (January and February) , than during the hottest months (May -July).…”

Section: Resultscontrasting

confidence: 99%

Seasonal Variation in Serum T3 and T4 Levels in Man.

Smals

Ross

Kloppenborg

1977

The Journal of Clinical Endocrinology & Metabolism

View full text Add to dashboard Cite

show abstract

Section: Resultscontrasting

confidence: 99%

Seasonal Variation in Serum T3 and T4 Levels in Man.

Smals

Ross

Kloppenborg

1977

The Journal of Clinical Endocrinology & Metabolism

View full text Add to dashboard Cite

show abstract

“…In addition, serum/plasma TT3 or TT4 levels were inversely related to the seasonal changes in ambient temperature (Nicolau & Haus, 1992). Simoni et al, (1990) and Postmes et al, (1974), on the other hand, could not detect a significant seasonal variation in FT4 or TT3, respectively. A low-amplitude circannual rhythm of plasma glucocorticoid secretion has been suggested in adult humans (Agrimonti et al, 1982).…”

mentioning

confidence: 74%

Components of biological variation, including seasonality, in blood concentrations of TSH, TT3, FT4, PRL, cortisol and testosterone in healthy volunteers

Maes

Mommen

Hendrickx

et al. 1997

Clinical Endocrinology

203

120

View full text Add to dashboard Cite

show abstract

“…In another study, the highest circannual values of thyroid hormones were found in August-October in France (Pas¬ quali et al 1984), but there was no variation in Holland (Postmes et al 1974) or in Japan (Konno et al 1982).…”

Section: Discussionmentioning

confidence: 97%

Serum concentrations of thyrotropin, thyroxine, triiodothyronine and thyroxine binding globulin in female endurance runners and joggers

Hohtari

Pakarinen

Kauppila

1987

Acta Endocrinologica

View full text Add to dashboard Cite

The effects of endurance training and season on the function of the anterior pituitary-thyroid axis were studied in 18 female runners and their 12 controls, and in 13 joggers and their 11 controls in Northern Finland, with a large seasonal difference in environmental factors. The serum concentrations of thyrotropin (TSH), thyroxine (T4), free thyroxine (fT4), triiodothyronine (T3), thyroxine binding globulin (TBG) and oestradiol (E2) were measured during one menstrual cycle in the light training season (autumn) and in the hard training season (spring). The responses of TSH to intravenous TRH stimulation were also measured in the luteal phase of the cycle during the hard training season. Endurance running did not affect the basal or TRH-stimulated serum TSH concentrations, while those of T4 and fT4 in runners were lowered in both seasons and that of T3 in the light training season in relation to control subjects. The serum concentrations of TBG were also significantly lower in runners than their controls in the luteal phase in both seasons. The effect of jogging on thyroid hormones was less pronounced. Serum concentrations of TSH, T4, fT4, T3 and TBG were generally slightly higher in spring than in autumn. Strenuous endurance training seems to have minor changes on the function of the thyroid gland. Depressed T4 levels in runners may rather be due to lowered TBG levels than due to direct effect of training. In spring the function of anterior pituitary-thyroid axis is more active than in autumn.The hypothalamic-pituitary-thyroid axis is sensi¬ tive to stress. During pregnancy the function of the thyroid gland increases (Burrow 1975), while in non-thyroidal illnesses, including infections, renal and hepatic diseases and starvation, the serum concentration of triiodothyronine (T3) de¬ creases and that of serum thyroxine (T4) show minor alterations (Schimmel et al. 1977).Endurance training is a hard physical stress which decreases the amount of body fat and increases demands on the energy supply, and which is partly regulated by thyroid hormones. Secretion of thyrotropin (TSH) is also under the stimulatory control of oestrogens (Labrie et al.1978), the concentrations of which, however, are decreased in female runners (Boyden et al. 1983;Ronkainen et al. 1985). Physical exercise may thus affect the function of the anterior pituitary-thy¬ roid axis of women by different mechanisms. The effects of such training on the pituitary-thyroid axis have been evaluated only in few investiga¬ tions, dealing with ballet dancers (Warren 1980) and runners (Boyden et al. 1982(Boyden et al. , 1984Marcus et al. 1985). The results in these studies have been conflicting; decreased, unchanged or increased responses of TSH and thyroid hormones to stre¬ nuous exercise have been reported.To gain information on the association of the function of the pituitary-thyroid axis and chronic, intense training in women, we measured serum concentrations of TSH, thyroid hormones, thyro¬ xine binding globulin (TBG) and oestradiol (E2) of runners, jogge...

show abstract

A radioimmunoassay study and comparison of seasonal variation in plasma triiodothyronine and thyroxine concentrations in normal healthy persons

Cited by 17 publications

References 10 publications

Seasonal Variation in Serum T3 and T4 Levels in Man.

Seasonal Variation in Serum T3 and T4 Levels in Man.

Components of biological variation, including seasonality, in blood concentrations of TSH, TT3, FT4, PRL, cortisol and testosterone in healthy volunteers

Serum concentrations of thyrotropin, thyroxine, triiodothyronine and thyroxine binding globulin in female endurance runners and joggers

Contact Info

Product

Resources

About