THYROTROPHIN POTENCY OF TRANSPLANTABLE PITUITARY TUMORS OF MICE THROUGH FOUR TRANSFERS

Abstract

IN RECENT years, several different types of transplantable, functional pituitary tumors have been developed in mice and rats (1 and 2). Most remarkable among these are the transplantable thyrotrophic pituitary tumors which can be induced by radiothyroidectomy, surgical thyroidectomy, or blocking of thyroid hormonal synthesis by anti-thyroidal compounds. Earlier studies have shown that the thyrotrophic tumors have a high hormonal content. Most studies, to date, have, however, been of the physiological nature of the tumors and histological techniques have been used to describe the tissue changes that occurred. The following study for the first time records weight changes in various endocrine organs and gives quantitative values for the concentration of thyrotrophin in the tumors and the blood of the mice through successive generations of transplantation. Mice: All mice used were of the C57B1. strain. After 2-3 weeks on a low iodine diet