The thyroxine ‘receptor’ of the thyroid‐pituitary system

Modulation of Pituitary Responsiveness to Throtropin-Releasing Hormone by Triiodothyronine

“…Total and free T4 levels were normal in all. TRH administration was performed before the instituThe Journal of Clinical Investigation Volume 52 January 1973 10,20,30,40, 60, 90, 120, and 180 min, centrifuged, and the plasma frozen until assayed. T3 (7) and TSH (9) were measured by radioimmunoassay; T4 was determined by competitive protein-binding analysis (Boston Medical Lab., Boston, Mass.…”

The role of hypothalamo‐hypophysial connexions in thyroid secretion

“…Minor modifications have been introduced which are described in the accompanying paper (Euler & Holmgren, 1956). …”

“…However, there has been much dispute about the afferent part of the systems; whether the sensitivity to the blood level of the target hormones is a property of the anterior pituitary itself or of a 'receptor' mechanism located in the brain stem. In the preceding paper we have presented evidence in favour of a pituitary location of the mechanism sensitive to thyroid hormone (Euler & Holmgren, 1956). If this conclusion is correct, pituitary grafts in hypophysectomized animals should, if showing functional activity, respond to changes in the level of circulating thyroxine.…”

Urinary Excretion of TRF in Various Functional States of the Thyroid

“…Von Euler and Holmgren (1956, a), however, observed the inhibition of TSH secretion together with decrease in the blood level of thyroxine,after the local injection of thyroxine into the adenohypophysis,and stated a possibility that thyroxine acts upon adenohypophyseal level directly and not through feed back control by the hypothalamus. Ottaviani and Azzali(1956), Azzali (1956) found a lipoid factor controlling the thyroid gland presenting in the hypothalamus.…”