382 THE PHYSIOLOGY OF REPRODUCTION 



who states that the changes in the pituitary were similar to those 

 occurring after removal of the thyroids. Taiuller and Gross 1 have 

 described pituitary hypertrophy in castrated men. The condition 

 was found in the Skopzen sect of eunuchs and also in women after 

 ovariotomy. Hammond 2 has shown that pituitary hypertrophy occurs 

 in sheep after ovariotomy. It affects the glandular part or anterior 

 lobe only. Blair Bell 3 finds evidence of increased secretory activity 

 on the part of the anterior lobe of the pituitary after ovariotomy, 

 but in his experience the changes are slight and not quite constant. 

 They are not nearly so great as during pregnancy or after the removal 

 of the thyroids or suprarenals. According to Livingston 4 whereas 

 ovariotomy may cause hypertrophy of the pituitary in rabbits, the effect 

 of castration on that organ is negligible. According to Pepere, 5 there is 

 probably no specific hypertrophy of the hypophysis in relation to the 

 extirpation of any particular ductless gland in the organism, but 

 the reaction of the cellular elements, though varying in response to 

 different conditions, shows also many characters referable to a common 

 cause. 



Compte 6 showed that the anterior lobe undergoes hypertrophy 

 during pregnancy, the whole organ being increased in weight at 

 the end of the period. Erdheim and Stumme 7 confirmed and 

 extended the observations. The changes are due mainly to the 

 accumulation of the " pregnancy cells " which are derived from the 

 chromophobe or chief cells. Blair Bell 8 regards these pregnancy 

 cells as being correlated with an immediate demand for increased 

 secretion. The secretory products appear to pass over, at anyrate to 

 some extent, to the posterior lobe. Pituitary hypertrophy during 

 pregnancy may be so great as to cause pressure on the optic chiasma 

 and transient pathological symptoms which disappear later when the 

 gland returns to the normal condition. 



It has been shown, as will be described more fully in the chapter 

 on lactation (p. 621), that extract of posterior lobe when injected into 



1 Tandler and Gross, "Einfluss der Kastration, etc.," Wien. klin. Woch., 

 vol. xx., 1907. Tandler, " Untersuchungen an Skopzen," Wien. klin. Woch., 

 vol. xxi., 1908. 



2 Hammond, " The Effect of Pituitary Extract on the Secretion of Milk," 

 Quar. Jour. Exp. Phys., vol. vi., 1913. 



3 Blair Bell, loc. cit. 



4 Livingston, " Effect of Castration on Weight of Pituitary in Rabbits," 

 Proc. Soc. Exp. Biol. and Med., vol. xi., 1914 ; and Amer. Jour. P'hysioL, vol. xl., 

 1916. 



5 Pepere, " Sur les Modifications de Structure du Tissu Parathyroidien 

 normal et accessoire (thymique) en rapport avec sa Fonction vicariante," Arch, 

 de Med. Exper., vol. xx., 1908. 



6 Compte, Contribution a V Etude de Hypophyse, etc., Lausanne, 1898 ; and 

 Beitr. zur Path. Anat., etc., vol. xxiii., 1898. 



7 Erdheim and Stumme, " Ueber die Schwangenschaftveraenderung der 

 Hypophyse," Beitr. zur Path. Anat., etc., vol. xlvi., 1909. 



* Blair Bell, loc. cit. 



