368 THE DUCTLESS GLANDS 



pituitary, produces a marked fall of blood -pressure. The 

 precise significance of this is difficult to understand. 



It is yet too early for us to be able to determine the value of 

 these antiserum experiments. 



L. Chemistry of the Pituitary Body 



Schafer and Vincent, who described a pressor and a depressor 

 substance, found that the latter could be separated from the 

 former, on account of the fact that it is soluble in alcohol, in 

 ether, and in normal saline solution. This is of course the 

 depressor substance common to all animal tissues. 



Schafer and Herring contend that two active principles exist 

 in pituitary extracts, one acting on the circulatory system, the 

 other specifically on the kidney. Dale does not consider the 

 evidence on this point to be satisfactory. 



Within recent years three observers have claimed to have 

 obtained, apparently independently, the active substance in a 

 pure form. Houssay, in 1911, prepared the active substance as 

 follows : " The fresh hind lobes were boiled in water ; the 

 filtrate was then precipitated with lead acetate and sulphuric 

 acid, filtered, and the filtrate dried in vacua. The residue is 

 washed with chloroform, ether, and alcohol, and finally crys- 

 tallized in vacuo. The product is insoluble in alcohol, ether, 

 or chloroform, but very soluble in water, and is dialy sable. It 

 is precipitated by picric acid, platinum chloride, etc. If burnt 

 on platinum foil, it gives off the smell of burnt feathers." 



Solutions of this product in normal saline produce the effects 

 of pituitary extracts upon the heart and vessels. 



Fiihner claims as well to have isolated a pure crystalline 

 basic substance, which has been put upon the market in the 

 form of its sulphate, and is called hypophysin. Fiihner 's 

 product is said to possess all the activities of pituitary extracts 

 on respiration, blood-pressure, and the uterus. 



Herzberg has tested Fiihner's substance clinically, and reports 

 that its action upon the uterus is powerful and prompt. 

 " Hypophysin " is stated to consist of four separate substances. 



In still later papers, Fiihner and Schickele declare that the 

 substance acting upon the uterus is independent of that acting 

 upon the blood-pressure, and can be obtained from extracts of 

 the anterior as well as of the posterior lobe. 



