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the extremities, hands and feet. To this phase of pituitary activity the term 

 hyperpituitarism has been given. 



The opposite condition, infantilism and adiposity, have also been shown 

 to be associated with pathologic changes in the pituitary. In these cases 

 not only is the individual of small size but the genital organs are undeveloped. 

 In addition there may be a subnormal temperature, loss of hair, etc. These 

 phenomena are believed to be due to a diminished or defective secretion 

 partly of the anterior lobe and partly of the posterior lobe. To this condi- 

 tion the term hypopituitarism has been given. 



The Effects of Removal of the Posterior Lobe. Gushing in a series of ex- 

 periments (1911) has demonstrated that the posterior lobe with its epithelial 

 investment exerts, contrary to general opinion, a profound influence on 

 metabolism and more especially on the metabolism of the carbohydrates, 

 either alone or in conjunction with other glands having internal secretions, 

 as will be explained more fully in a following paragraph. These experi- 

 ments also led to the belief that some of the phenomena detailed in the 

 foregoing paragraph, especially the deposition of fat, the subnormal tem- 

 perature and perhaps the imperfect development of the sexual organs are 

 due rather to a deficiency or absence of the secretion of the posterior lobe 

 than to a deficiency or absence of the secretion of the anterior lobe. 



It has apparently been demonstrated by Gushing that the hyaline bodies 

 found in the posterior lobe represent an internal secretion; that they are 

 discharged into the cavity of the third ventricle where they undergo solution 

 in the cerebro-spinal fluid, by means of which the dissolved material 

 enters the blood-stream. The presence in the cerebro-spinal fluid of an 

 agent that produces the same physiologic effects when intravenously in- 

 jected, as injections of extracts of the posterior lobe do, has also been 

 established. 



In the various operative procedures incident to the removal of the entire 

 hypophysis or of the anterior lobe a transient glycosuria is frequently ob- 

 served, a phenomenon attributed to the discharge under the circumstances of 

 an excessively large amount of the reserve hyaline substance or of the 

 posterior lobe secretion into the third ventricle. This secretion in some 

 unknown way leads to a hyperglycemia and glycosuria. At the same time 

 the animal becomes unable to tolerate or assimilate the usual amount of 

 sugar experimentally ingested without increasing the glycosuria, which is 

 assumed therefore to be of alimentary origin. 



If the posterior lobe with its epithelial investment is totally removed 

 or if the infundibular stalk is compressed by a clip so as to prevent the dis- 

 charge of the secretion into the ventricle the animal becomes very tolerant of 

 sugar and is enabled to assimilate larger quantities than formerly without 

 the development of alimentary glycosuria. As a probable result of the in- 

 creased carbohydrate assimilation, a condition of nutrition is established, 

 characterized by a general deposition of fat suggesting a conversion of the 

 sugar into fat. There is probably at the same time an imperfect oxidation 

 of the carbohydrates as indicated by the lowered temperature. 



That the condition of generalized adiposity is probably due to deficient 

 posterior lobe secretion is shown by the fact that the increased tolerance for 



