Abstract
Effect of goitrin upon thyroid function was investigated in body weight gain and nitrogen balance with both immature rats weighing about 80g and mature rats about 240g. Various amounts of goitrin, 1 to 20mg per rat per day, were administered orally for a period of 14 days.
Thyroid weight increased and plasma PB131I decreased proportionately to the quantity of goitrin administered and suppression of thyroid function was observed. Body weight gain of immature group administered with 20mg goitrin was depressed but mature group administered with 20mg goitrin showed a tendency to increase. In other groups, administration of goitrin gave no effect on body weight gain.
It was decreased in nitrogen retention of immature rats but showed a rising tendency in mature rats by goitrin administration. Though correlation between nitrogen retention and thyroid function was observed to be insignificant in this experiment, weight and nitrogen content of liver increased in the goitrin administered groups and significant correlation was observed between liver nitrogen and thyroid function.
Differences of thyroid function, body weight gain and nitrogen retention were discussed between immature and mature rats.
