EFFECT OF EXCESS IODIDE UPON ANTERIOR PITUITARY CYTOLOGY OF THE COMPLETELY THYROIDECTOMIZED RAT AND ITS BEARING ON THE QUESTION OF EXTRATHYROIDAL THYROXINE SYNTHESIS 1
1951; Oxford University Press; Volume: 49; Issue: 1 Linguagem: Inglês
10.1210/endo-49-1-21
ISSN1945-7170
AutoresR. F. HUM, R. C. GOLDBERG, I.L. Chaikoff,
Tópico(s)Growth Hormone and Insulin-like Growth Factors
ResumoALTHOUGH cytological changes in the anterior pituitary after thyroidectomy were observed as early as 1889 (Rogowitsch), it has only recently been shown that the state of the acidophils in the rat anterior pituitary is related to the level of circulating thyroxine. Thus, Greisbach and Purves (1945) and Goldberg and Chaikoff (1950a) demonstrated that in the totally thyroidectomized rat, the acidophils constitute only about 1 per cent of the total adenohypophyseal cells, in contrast to a normal value of approximately 40 per cent. The daily administration of 0.5 gamma of DL-thyroxine per 100 gm. body weight does not prevent the appearance of typical thyroxine deficiency changes in the basophils of the thyroidecto-mized rat, but does keep the acidophils normal as judged by their morphological appearance and their percentage. The sensitivity of the acidophil response to thyroxine is most clearly brought out by comparing the effects of smaller doses; the daily injection of 0.25 gamma DL-thyroxine per 100 gm.
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