THE PITUITARY BODY 



Recently, a number of authors have studied the pituitary 

 of the pregnant rat. OxyphiHc cells with homogeneous or 

 finely granular protoplasm are said to be characteristically 

 present in the pars glandularis (Schenk, 1926; Lehmann, 

 1928; Haterius, 1932; Charipper, 1934; and Desclin, 1934). 

 Wolfe and Cleveland (1933). however, doubted that any 

 particular cell type was peculiar to pregnancy in the rat; they 

 described complex qualitative and quantitative changes in 

 all the cell types. Severinghaus (1934) declared that the 

 pregnancy-cell is a modified (degranulated) basophil which 

 other investigators have confused with reserve cells or with 

 altered oxyphils. The results so far mentioned cannot be 

 reconciled with those of Stein (1933-34), who reported that 

 no qualitative or quantitative change in the cytology of the 

 pars glandularis occurred in pregnant rats. He found that the 

 proportion of reserve cells, oxyphils, and basophils was al- 

 tered neither in primiparous nor in multiparous normal rats. 

 Unlike the pituitary of many mammals, that of the rat not 

 only does not enlarge during pregnancy (Stein), but also may 

 become smaller (Herring, 1920). According to Stein the pars 

 neurahs may be hypertrophied in multiparous rats. 



In the mouse, rat, and guinea pig the pregnancy changes 

 in the pituitary have been attributed to the internal secretion 

 of the corpus luteum (Brouha and Desclin, 1931; Haterius 

 and Charipper, 1931; Haterius, 1932; Desclin, 1932-33; 

 Brouha, 1934; Charipper, 1934). The changes may be pro- 

 duced in non-pregnant females or in males with transplanted 

 ovaries by causing luteinization (with resulting increased 

 corpus luteum secretion) of the ovarian tissue. The adminis- 

 tration of corpus luteum extract to normal, castrated, or 

 spayed animals is also said to provoke pregnancy-like changes 

 in the pars glandularis. 



Haterius (1932) found that the pituitary of lactation re- 

 sembled that of pregnancy in the rat. After weaning and 

 with the onset of oestrus, the oxyphil cells with homogeneous 



