Changes in the Anterior Pituitary Gland of Rats With Experimental Goiter. II

Abstract

In a previous communication 1 cellular changes in the anterior lobe of the pituitary gland of rats reared on a goitrogenic diet 2 were described. In male rats fed for 3 to 12 months on the Steenbock and Black diet 3 supplemented by viosterol, nests of large cells were seen in the anterior lobe of pituitary glands fixed in Bouin solution and stained with hematoxylin-eosin. We report now the results of histologic examinations of pituitaries which had been fixed in Regaud solution and were stained with methods which permit the identification of granules as well as that of other elements contained in the cytoplasm of the abnormal cells. During life the rats had been treated for 4 to 12 months in the same way and fed the same diet as the animals described before.

On sections of pituitaries fixed with Regaud solution and stained with hematoxylin and eosin, groups of large cells can be recognized with the low power objective of the microscope; the picture resembles that of pituitaries fixed with Bouin solution. With the high power magnification the large cells appear to contain vacuoles of different sizes. In animals on the diet 4 to 6 months numerous small vacuoles can be seen which give the cytoplasm a spongy appearance. In older animals the large cells often contain but a single large vacuole which is filled with a pale hyaline or colloid material (Fig. 1). Mitotic figures are occasionally seen in these cells (Fig. 2) suggesting a process of cellular hyperplasia.