96 ALBERT 0. CRAWFORD 



From a study of gold and platinum precipitates, Marino-Zuco claimed 

 to have proved the presence of neurin in these glands, but did not trace 

 all of their toxicity to it. From a study of his lead precipitates, Marino- 

 Zuco believed that various phosphoric acids, especially glycerophosphoric, 

 were present, but was unable to isolate them. When neurin was mixed 

 with these acid products, the toxicity of his mixtures corresponded to that 

 of the original extracts and as this toxicity was lost on treatment with 

 an acid, he believed that it was due to a phosphoric acid ester of neurin 

 (Guarnieri and Marino-Zuco). However, it is well to remember that for- 

 merly what was called neurin was confused with cholin (Dybkowski), and 

 later Oliver and Schafer found that the toxic symptoms from suprarenal 

 extracts were different from those produced by neurin, but Lohmann seems 

 to have shown the presence of at least small amounts of neurin in the cortex 

 of these glands. 



In 1897, Metzger extracted ground-up suprarenal glands with dilute 

 tartaric acid, concentrated on the water bath and evaporated to dryness 

 with pumice stone. The pulverized mass, on extraction with ether, yielded 

 a substance which gave weak suprarenal reactions, but did not reduce 

 gold chlorid. However, crystals were found on the walls of the flask, 

 which he said gave the iron-chlorid reaction and reduced gold. These 

 crystals resembled leucin and exerted a pressor action. This work has 

 not yet been corroborated. 



After dehydrating the desiccated cortex with sodium phosphate, Voegt- 

 lin and Macht, by extraction with anhydrous chloroform, obtained crys- 

 talline platelets, which melted at about 50 C. These exerted a vaso- 

 constrictor action on frog blood-vessels and a digitalis-like action on the 

 heart. 



Years ago, I tried on suprarenal extracts the method which I had 

 used for extracting a pressor compound from an American mistletoe, i. e., 

 dehydrating and alkalinizing an aqueous extract with a large excess of 

 calcined magnesium oxid, then shaking with anhydrous ether and pre- 

 cipitating with an ethereal solution of oxalic acid. This method yielded 

 a white precipitate which, in the amounts used, produced no noticeable 

 rise in the blood pressure of dogs and was not studied further. 



Microscopists have called attention to droplets in the suprarenal cor- 

 tex some of which, unlike fats, are soluble in chloroform, or oil of ber- 

 gamot after previous treatment with osmic acid (Rahl), and unlike fats are 

 doubly rcfractile (anisotropic) ( Kaiserling and Orgler). Some do not stain 

 black with osmic acid (Alexander), some, at least, do not dissolve in al- 

 kalies (Moors), hence have been grouped under the name lipoids. The 

 term Hpoid must necessarily be rather indefinite and embrace a number 

 of ill defined substances. 



Stearic and palmitic acids, the phosphatid, sphingomyelin and the 

 phosphorus-free galactosid, phrenosin, have been obtained from the cortex 



