PLASMA THYROTROPHIN LEVELS IN THYROID DISEASE AND EFFECT OF TREATMENT
ABSTRACT A radioimmunoassay has been developed and was applied in a first study to the determinations of human plasma TSH in normal subjects. In the present work a systematic study was made of the relation between the pituitary and the thyroid gland in thyroid disease, and on the effect of various forms of treatment in 750 patients. Normal values for adults of both sexes were found to be 0.19 mU/ml, referred to the international bovine TSH standard (USP). No TSH was found in pituitary hypothyroidism. Elevated levels, up to fifteen times those of normal subjects, were found in myxoedema. The low initial values in all forms of thyrotoxicosis were followed by modifications during treatment depending on the kind of treatment used. Every qualitative or quantitative deficiency of thyroid hormone secretion was accompanied by an elevation of TSH (euthyroid nodular goitre, thyroid carcinoma, subacute thyroiditis and Hashimoto's disease) and treatment with thyroid hormones induced a rapid fall in plasma TSH. The action of lysine vasopressin was also studied.