764 FREDERICK S. HAMMETT 



These positive observations would tend to support Gushing' s (1912) opin- 

 ion that th^ posterior lobe of the hypophysis has a glycogenolytic function. 

 Kojima's (1911) report is interesting in this connection from the fact 

 that he obtained changes in the pancreas as the result of feeding pituitary. 

 On histological examination of the pancreas of the experimental animals he 

 found that many of the cells of that tissue had undergone vacuolization ; 

 that there was an edema of the entire organ, excepting the isles of Langer- 

 hans, and that these were crowded with granules. 



Effects on Secretions and Lactation. Turning now to* a brief pres- 

 entation of the effect on other secretory functions it is found that both 

 Eogers (1915-16) and his collaborators and Pal (1916) have obtained an 

 inhibition of the flow of gastric juice as a result of the administration of 

 posterior lobe extracts, and Wiggers (1911) reports a similar inhibition 

 of pancreatic secretion. Solem and Lommen (1915) found that the drug 

 caused a diminution of the flow of saliva and also of the blood through the 

 salivary glands. Since the retardation of the salivary flow was greater 

 than that of the circulation through the gland they concluded that the ex- 

 tract inhibits the action of the secretory nerves to the gland as well as 

 causes vasoconstriction. 



The stimulating effect of posterior lobe extracts on the lactating mam- 

 mary gland was first observed by Ott and Scott(a)(&) (1910) and con- 

 firmed by MacKenzie (1911), Schafer and MacKenzie (1911), Houssay 

 and Maag (191-1) and others. This was shown to be a common reaction in 

 many types of mammals by Simpson and Hill (1914-15), Hill and Simp- 

 son^) (&)(c) (1913-14), Hughes (1915) and others. Hofstatter (1919) 

 claims that the long continued administration of posterior lobe extract 

 causes a development of the mammary glands; Bell (1919) was unable to 

 show definitely such developments in virgin animals. The stimulative ef- 

 fect on lactation is rapid but transitory in nature. The milk expressed at 

 the time is usually of a greater fat content than normal though this is de- 

 nied by McCanlish (1918). There is a tendency to a lessened milk secre- 

 tion the day after the effect of the extract has been tested. Hammond 

 (1913) is of the opinion that the increased milk flow is a true secretory 

 phenomenon and not due to any rise in blood-pressure, basing his opinion 

 on the higher fat content of the milk. Maxwell and Rothera (1915) agree 

 with the idea of the secretory nature of the stimulus. Schafer (c) (1915) 

 opposes this conception and considers that the effect is not a true secretory 

 stimulation but is a simple squeezing out of the milk by the contraction of 

 the muscles of the alveoli and ducts. This opinion is supported by the 

 observations of Gaines(a)(&) (1914-15), who has found that the flow 

 depends on the amount of milk in the gland and that the reaction can be 

 obtained from the excised gland. He is accordingly of the belief that the 

 action is not a true secretory stimulation, but is merely the constrictor 



