| 7293669 |
Stringer B, Wynford-Thomas D, Jasani B, Williams ED: Effect of goitrogen administration on the circadian rhythm of serum thyroid stimulating hormone in the rat. Acta Endocrinol. 1981 Nov;98(3):396-401.
Adult male rats were fed a goitrogen, aminotriazole, for 74 days at a dose known to suppress thyroid function completely. At the end of this period, these animals along with matched controls were killed in groups of seven at 3 hourly intervals throughout a 24 hour period, and serum TSH, T3, T4 and albumin assayed. No significant circadian rhythms of T3, T4 or albumin were found in either, but a highly significant rhythm of TSH was demonstrated both in controls and goitrogen treated groups, with a diminished relative amplitude in the latter. The results indicate that a significant diurnal rhythm of serum TSH persists in the rat despite long-term blockade of thyroid hormone synthesis and that the existence of this rhythm is therefore independent of the presence of circulating T3 or T4. |
1(0,0,0,1) |