Responses of the Normal Human to Infusions of Plasma from Patients with Graves' Disease*

Abstract

The purpose of the studies which are reported was to determine if the plasma of patients with Graves'' disease contains a factor distinct from thyrotropin which stimulates organic iodine metabolism in the normal human. The effects of various doses of commercial bovine thyrotropin and the infusion of plasma from a patient with spontaneous myxedema and from patients with Graves'' disease who were either hypothyroid, euthyroid or hyperthyroid at the time of donation were recorded using a new, sensitive model for the study of thyroid stimulating substances in man. The results indicate that there is such a factor and because the responses obtained in man grossly resemble those previously observed in animals, the responsible plasma component is presumed to be the long-acting thyroid stimulator (LATS). Evidence is also given which suggests that in Graves'' disease, the thyrotropin secreting mechanism of the pituitary is subject to the well recognized negative feedback control related to blood thyroxine concentration but that the production of the thyroid stimulator peculiar to Graves'' disease is not.