166 GROWTH 



An adult afflicted with posterior lobe hypopituitarism is 

 tolerant to sugars. He produces an excess of fats which are de- 

 posited in large amounts subdermally in special regions of the 

 body, which actually distort his proportions. Great aprons of fat 

 occur on the chest and abdomen and to a lesser extent on the 

 hips and legs. Extreme cases look like monsters. 



It is not desirable to discuss the matter in too great detail but 

 it gives some idea of the difficulties the physiologist must sur- 

 mount in experimental testing to remember the location and 

 structures of the pituitary organ. This small endocrine gland in 

 the human is a mass less than one cubic centimeter in volume 

 and weighs only 0.6 of a gram. It is richly supplied with blood 

 vessels. Embryologically the pituitary consists of two lobes or 

 parts. The posterior lobe grows from embryonic brain tissue, 

 the anterior lobe is from the tissue that gives rise to the walls 

 of the mouth and pharynx. It is the anterior part that produces 

 the hormone which induces gigantism, while the posterior part 

 interferes in part with the chemical fate of and increases the 

 tolerance for sugars expressed by an enormous sugar appetite. 



Very active preparations of extracts of the posterior pituitary 

 lobe have been produced and have been listed among commer- 

 cial drugs for some years under the name of fituitrin. Dr. Abel 19 

 of Johns Hopkins University has contributed most toward the 

 identification of the posterior pituitary lobe hormone. He 

 classes this substance as an amino acid derivative, a histamine- 

 like body. Recently he isolated a pituitary tartrate so intense in 

 action that it produces a measurable physiological change in 

 dilutions of one part in 18,750,000,000. This is equivalent to 

 1 gram dissolved in 18,750,000 liters of water, a volume not 

 less than 50 times the total capacity of this (the Physics) lecture 

 room. This is the most vigorously active physiological substance 

 known at the present time. 



The facts presented in the preceding discussion are largely 

 those observed in the human. They are confirmed and extended 

 by experimental observations on lower animals. Both the human 



