114 The Lymphocyte and Lymphocytic Tissue 



small lymphocytes (Figs. 9-1, 9-2). Tiny pycnotic cells are absent, and there 

 is an increase of cell size to that of a medium-sized, mature lymphocyte with 

 a wide rim of clear cytoplasm. The cells do not appear to be more immature 

 in that they do not acquire an increased nucleolar number or a more lepto- 

 chromatic fineness of the chromatin pattern. 6 The cytoplasm increases in 

 amount and appears very hyaline with a loss of cytoplasmic basophilia. 



+**>*• 



• <hP* 



Fig. 9-5. Phagocytosis of nuclear and cytoplasmic debris by fixed reticuloendo- 

 thelial cells in medulla of inguinal node following ACTH treatment. Hematoxylin- 

 eosin stain, (x 1350) 



» ' ^ ft 



i 



The cells are closely packed in the node (Figs. 9-1, 9-2). There is also a 

 general tendency to have indefinite germinal centers in that there is no sharp 

 demarcation of the difference between the large cells in the germinal center 

 and the collar of lymphocytes about it. fi Numerous mitoses are found, and 

 studies of DNA renewal in this laboratory support the observation that there 

 is a true increase in rate of proliferation as compared to nonoperated 

 controls. 2 



The nitrogen content per unit weight of lymphatic organs of adrenalecto- 

 mized mice does not increase. 7 Therefore it is apparent that the larger 

 lymphocytes in adrenalectomized animals do not contain more protein per 

 cell. This increase in cell size is probably due to increased intracellular 



