EFFECTS OF INANFflON AND REFEEDING UPON THE 



(iROWTH AND STRUCTURE OF THE 



HYPOPHYSIS IN THE 



ALBINO RAT 



C. M. JACKSON 



Inxiitute of Anatomy, University of Minnesota, Minneapolis 



FIVE FIGURES 



CONTENTS 



Material and methods 322 



Relative volumes of the jjarts (lobes) 327 



a. In normal growth 327 



b. In young rats held at maintenance 331 



c. In acute and chronic inanition in adults 332 



d. In stages of refeeding after maintenance 332 



Volumetric analysis of tissues and cells in pars anterior 333 



a. Relative volumes of stroma and parenchyma 333 



b. Relative volumes of nuclei and cytoplasm 334 



c. Estimated size of cells and nuclei 335 



Direct measurement of nuclear diameters 337 



Occurrence of mitosis in the parts (lobes) 339 



a. In normal growth 341 



b. In young and adult rats during inanition 343 



c. In various stages of refeeding after maintenance 343 



Changes in histological structure 344 



a. Pars nervosa 344 



b. Pars intermedia 345 



c. Pars anterior 347 



d. Changes during refeeding after maintenance 350 



Discussion and conclusions 351 



Summary 354 



Literature cited 357 



On account of the intimate relations usually assumed to exist 

 between the hypophysis and the general growth process of the 

 body, the effects of inanition and refeeding upon this organ have 

 unusual interest and importance. Few observations upon these 

 effects are recorded in the literature. In previous papers (Jack- 



321 



THE AMERICAN JOIUXAL OF AN'ATOMV, VOL. 21, XO. 2 



