HYPOPHYSEAL MORPHOLOGY 



201 



positive PAS reaction for glycoprotein 

 (Herlant, 1958). Romeis noticed that some 

 of the /?-cells retained azocarraine during 

 the azan staining of the sections previously 

 stained with resorcin-fuchsin, whereas others 

 retained only a blue counterstain from the 

 aniline blue. The researches of Griesbach 

 (unpublished) have convinced me that these 

 staining reactions indicate two distinct 

 types of cell whose granules are stained 

 by resorcin-fuchsin, i.e., two types of ^- 

 cells. After Helly fixation the difference 

 between the two types is enhanced. Also 

 after Helly fixation the staining of the gran- 

 ules of one type of ^-cell by aldehyde- 

 fuchsin is greatly weakened, an effect which 

 allows the red counterstain by azan in this 

 type to be more clearly seen. The y8-cells 

 are therefore seen to comprise purple AF 

 cells and blue AF cells. These we may call 

 in the human pars distalis "purple /3" and 

 ''blue ^." The 8-cells are blue non-AF after 

 Helly fixation, and the y-cclls are usually 

 also blue non-AF. 



The blue /?-cells are more variable in 

 size and shape than the purple /?-cells and 

 are more often found in multinucleated form 

 than the latter. Their distribution in the 

 gland is quite different from that of the 

 purple /?-cells, so that they cannot be vari- 

 ants of a single cell type. Moreover, the 

 staining reactions of the granules, except 

 to resorcin-fuchsin or aldehyde-fuchsin 

 after certain fixatives, are quite distinctive. 

 There are indeed more dissimilarities be- 

 tween purple /3-granules and blue /3-gran- 

 ules (Fig. 3.19) than there are between the 

 latter and the 8-granules. 



Reasons have been given in the section on 

 the pars intermedia and intermedin secre- 

 tion for regarding the purple /?-cells as in- 

 termedin-secreting cells corresponding to 

 the pars intermedia cells of the usual mam- 

 malian hypophysis. The blue /?-cells, the 8- 

 cells, and the y-cells should therefore be 

 homologous with the three basophil cell 

 types in the pars anterior of such mammals 

 as the rat, bat, and dog. 



C. DIFFERENTIAL STAINING OF BASOPHIL 

 CELLS IN THE HUMAN PARS DISTALIS 



The y-cells of Romeis are distinctive in 

 appearance, containing fine glycoprotein 



granules which are stained only feebly by 

 acid dyes (Figs. 3.20 and 3.21). In addition 

 they often contain droplets of glycoprotein, 

 intensely stained by the PAS reaction. These 

 cells have been termed "vesiculate chromo- 

 phobes" (Pearse, 1952) . They are not likely 

 to be confused with normally granulated jS- 

 cells or 8-cells. The partition of the basophil 

 cells by differential staining of the specific 

 granules is therefore a partition of the purple 

 ^-cells, blue ^-cells, and 8-cells (Fig. 3.22). 

 Some of the methods used produce a differ- 

 entiation between the purple ^-cells and the 

 two types of blue cells. Because it was as- 

 sumed that only two types of cell were in- 

 volved, the distinction between purple and 

 blue cells has been assumed to be a dis- 

 tinction between /S- and 8-cells. Purves 

 and Griesbach (1957b) observing purple 

 and blue cells in Crossmon (1937) stained 

 sections of human pars distalis wrongly 

 assumed this to be a distinction between 

 13- and 8-cells. Herlant (1953b; 1954b) dif- 

 ferentiated the purple /?-cells from the other 

 types by counterstaining PAS stained sec- 

 tions with orange G. The orange G stained 

 the strongly acidophilic granules of the 

 purple /3-cells and combined with the PAS 

 color to produce a brick-red shade whereas 

 the other basophil granules were magenta. 

 Wilson and Ezrin (1954) used a method 

 substantially the same as Herlant's PAS 

 orange method with the addition of methyl 

 blue. The methyl blue stained only the 

 magenta granules of Herlant leaving the 

 granules of the purple ^-cells brick-red. 

 The purple cells of Purves and Griesbach, 

 the brick-red cells of Herlant, and the PAS- 

 red cells of Wilson and Ezrin are obviously 

 the same cells and belong to the group of 

 ^-cells. It is only when these staining meth- 

 ods are applied as counterstains to sections 

 in which /?-cells have been electively stained 

 by aldehyde-fuchsin, as in the method of 

 Griesbach, that the dual nature of the /3- 

 cells is revealed. 



Adams and Swettenham (1958) applied 

 aldehj^de-fuchsin or Alcian blue to sections 

 oxidized with performic acid and followed 

 this with PAS staining. Their R cells which 

 were red and not stained by aldehyde- 

 fuchsin are the purple ^-cells, their S cells 

 which were stained by aldehyde-fuchsin or 



