THE SUPRARENAL SYSTEM l8l 



1-2 : 1000 sublimate solution are added to the liquid containing 

 adrenalin when, after one to three minutes, a diffuse red color- 

 ation is seen which lasts for several hours. Comessatti employed 

 his method also as a quantitative test of the amount of adrenalin 

 present in the suprarenal. In his view, the red coloration is 

 due to the formation of ox.yadrenalin (Battelli), and is identical 

 with the red colour which adrenalin solutions acquire when 

 exposed for some time to the air. Of allied substances, pyro- 

 catechin gives a green reaction with sublimate, salicylic acid and 

 resorcin produce shades of red. According to Comessatti, this 

 reaction gives positive results with attenuated solutions, where 

 Vulpian's ferric chloride reaction is doubtful (0.0025 grm. 

 adrenalin : 1000; or, one drop adrenalin in twenty distilled water; 

 or, one drop adrenalin in 100 to 130 cm. 3 tap water). On the 

 other hand, K. Boas found that, in the case of even concentrated 

 extracts, the reaction did not take place at room-temperature, but 

 that it made its appearance only after boiling. 



Another chemical method of differentiating adrenalin is that 

 of Cevidalli. If hydrochloric acid is added to suprarenal extract 

 prepared with physiological saline solution, the albuminoids will 

 be precipitated; the filtrate is then rendered alkaline with NH 3 , 

 and a few drops of a concentrated solution of ferricyanide of 

 potassium are added, when a pinkish colour makes its appearance 

 which, after several hours, changes to a brownish black. By this 

 method, Cevidalli and Leoncini carried out a series of investi- 

 gations into the amount of adrenalin present in the suprarenals 

 after death from various causes. They found that the " docimasia 

 surrenale " is sufficient to decide the medico-legal question as to 

 whether death has taken place suddenly, or is the outcome of 

 prolonged illness. In the latter case, the reaction is weak, but it 

 is very strong after sudden death. 



The colorimetric method of A. Zanfrognini depends for its 

 results upon the fact that, where adrenalin is present, the brown 

 manganese dioxides are converted into the colourless lower oxides, 

 in the course of which the solution acquires a red stain. The 

 intensity of the colouring is proportional to the amount of 

 adrenalin present in the solution. The reaction is extremely 

 sensitive, and is clearly perceptible in a solution of i : 1,000,000; 

 it remains unchanged for hours ; and takes place independently 

 both of the reaction of the medium and the presence of 

 neutral salts. The reagent (3 grm. permanganate of potassium 

 dissolved in 24 c.cm. distilled water, with the addition of 8 c.cm. 

 lactic acid) is added drop by drop to the liquid containing 

 adrenalin, and it immediately loses its characteristic colour and 

 acquires a distinct pink coloration. An excess of the brown 

 reagent does not affect the result, the superfluity being 

 immediately carried off by the addition of a minimal quantity of 

 peroxide of hydrogen. The colorimetric result is ascertained by 



