THE ADRENALS AND CHLOROSIS. 89 



pigments in the intestine, some appearing to pass out through 

 the epithelial cells, while others advanced into the subepithe- 

 lial elements. He also found them in the venules of the villi, 

 the capillaries of the liver, the spleen, etc. 



If the question of absorption is still sub judice, what can 

 we say of the process through which iron combines with other 

 bodies to form hemoglobin? Yet there are general points of 

 a chemical nature which may assist us in determining the gross 

 lines of this process. Thus we know that when hemoglobin 

 is acted upon by acids in the presence of oxygen hsematin is 

 formed; and also that in the absence of oxygen a hcemochro- 

 mogen first appears which slowly loses its iron, the end-product 

 being hcematoporphyrin. In chlorosis the tissues probably play 

 in this connection the part of the acid usually employed in 

 laboratories to disintegrate hemoglobin: they abstract oxygen. 

 The imperfect condition of the blood involving reduced oxida- 

 tion, oxyhsemoglobin is not always formed, and arterial blood 

 fresh from the lungs, while still containing a large proportion 

 of this compound, though just sufficient, in some cases, to 

 insure continuation of the vital processes, also contains a 

 more or less great proportion of reduced hsemoglobin. Under 

 these conditions the avidity of the tissues for oxygen causes 

 them not only to absorb the one molecule of this gas from the 

 oxyhagmoglobin, but also to make up for the deficiency by 

 taking up oxygen from haemoglobin: i.e., the only remaining 

 source of supply. We thus have in the blood the precise con- 

 ditions required for the reaction outlined, namely: absence of 

 oxygen and a powerful deoxidizant, and therefore obtain as 

 end-results free iron and hematoporphyrin. But does free 

 hematoporphyrin appear in the blood when insufficiency of 

 the adrenals occurs? The urine alone can afford the desired 

 information, and the inquiry must therefore be turned in this 

 direction. 



Haematoporphyrin was found in small quantities in normal 

 urine and practically always in pathological urine by Garrod 29 

 and Stockvis, 30 while various authors, including MacMunn, 31 



29 Garrod: Journal of Physiology, vol. xvii, No. 5. 

 *>Stoekvis: Jahresb. f. Therap. Chemie, vol. xxiii, 1893. 

 81 MacMunn: Journal of Physiology, vol., 1885. 



