FSH, TSH, T3 and T4 changes in relation to plasma copper and zinc alterations during D-penicillamine administration in female Wistar rats

Zinc and copper are considered to antagonize each other in several organs, while they play a significant role in the regulation and function of many systems. D-penicillamine was administered to 19 female Wistar rats for 68 days, 1 g/d/kg B.W. Plasma copper and zinc levels, as well as serum T3, T4, TSH and FSH were measured at days 50, 53, 54, 58, 62 and 68. Copper concentration presented a significant decrease. Zinc showed an initial increase by day 54, followed by a subsequent decrease. FSH levels decreased, presenting a pattern identical with that of copper. T3 and —especially— T4 alterations were similar to that of zinc and copper, whereas TSH alterations were inverse to them. It is concluded that copper and zinc alterations, induced by d-penicillamine administration, can significantly affect pituitary sex hormones (TSH) and hypothalamic-pituitary-thyroid axis in rats.