94 ALBERT C. CRAWFORD 



Popielski suggested that epinephrin existed in some labile combination 

 with protein, while others thought that epinephrin might be derived from 

 decomposition products of the lipins of the cortex (Boruttan), but as yet 

 a mother substance for epinephrin has not been discovered. We have no 

 reports of a thorough study of the suprarenal glands for amino-acids or 

 their decarboxylation products. Leucin and tyrosin have been shown to 

 be present (Lohman). 



Chemistry of Chromaffin Tissue 



The medulla of the suprarenal glands stains yellow, or brown, with 

 chromic acid, hence is spoken of as chromaffin tissue. Tissues giving this 

 reaction are found in the carotid bodies and elsewhere associated with the 

 sympathetic nervous system (Gaskell, Stilling). However, unlike epi- 

 nephrin, extracts of sympathetic ganglia cause a fall in blood pressure 

 (Cleghorn). 



It is believed that epinephrin, or a derivative of it, is the cause 

 of this reaction, as a solution of potassium bichromate colors epinephrin 

 crystals a brown color and this has been shown to be due to the formation of 

 Cr0 2 (Borberg; Ogata and Ogata; Stoeltzner). The intensity of the 

 chromium reaction corresponds to the amount of epinephrin present (El- 

 liott and Tucket; Ciaccio; Schur and Wiesel). Vincent believes that 

 chromaffin tissue always yields epinephrin, or a substance with similar 

 pharmacological action. The work of Ogata and Ogata indicates that the 

 chromophil reaction is really a reduction due to epinephrin and they would 

 substitute the name adrenalin tissue for chromaffin tissue. 



Chromaffin tissue, in other localities than in the suprarenal glands, 

 has been tested for the presence of epinephrin. Mulon claimed that he 

 obtained a pressor effect from an extract of the carotid 'body of a horse. 

 But Frugoni's injections in rabbits produced only a fall. However, Vin- 

 cent believes it would be impossible to obtain a pressor response from carot- 

 id gland extracts as these glands contain so many tissues which would 

 produce a fall, which fall would mask any possible rise. 



Using the test on uterine and on intestinal muscles as their guide, 

 Fulk and Macleod claim that extracts of the retroperitoneal chromaffin 

 tissue reacts like epinephrin and such extracts raise the blood pressure 

 (Biedl and Wiesel). Wells suggests that the production of epinephrin 

 outside of the suprarenal glands may explain the discrepancies between 

 the anatomic changes in the suprarenals and the clinical manifestations of 

 a deficiency of epinephrin. 



Abel and Macht have isolated large amounts of epinephrin (about 

 5 per cent) from the secretion of the parotid gland of the tropical toad, 

 Bufo agua (Abel and Macht). However, "at no time in their life history 

 do the epithelial cells show any yellowing after treatment with chromate 



