Urinary Excretion of TRF in Various Functional States of the Thyroid

TRF Concentrations in Various Tissues Following Anterior Hypothalamic Lesions

“…As reported previously, TRF is produced in the anterior hypothalamus and excreted in the urine (Shibusawa et al, 1956a(Shibusawa et al, , 1959a. In the hypophysectomized animals injected with TRF the T/S I131 ratio and the thyroid weight exhibited different responses which lead to the conclusion that the hypothalamic factor TRF possessed in itself both metabolic and growth activities.The urinary excretion and distribution in the body of TRF, under various functional states of the thyroid were reported previously, suggesting a feed-back mechanism in which the rate of TSH secretion is controlled by the plasma level of circulating thyroidal hormones (Shibusawa et al, 1959b, c). TRF,which has been found in the anterior hypothalamus and urine, may also be demonstrated in the neurohypophysis, cerebrospinal fluid and blood.…”

Studies on the Tissue Concentrations of TRF in the Normal Dog

“…The amount of the urinary excretion of T9 depends on the functional state of the thyroid (Shibusawa et al, 1959 b). In rats, administration of TRF could prevent the pituitary atrophy induced by the section of the pituitary stalk, and prevent the decrease in the serum level of TSH, and the decline in the thyroid function (Nishi, 1959). With regard to rat whose pituitary was extirpated, the stimulating effect of T9 on the thyroid could no more be observed (Nishi, 1959).…”