Disturbances of Haemoglobin Synthesis in Lead Poisoning 



We should like to insist, with Prader, on the analogy of the clinical 

 observations of anaemia to the appearance of protoporphyrin in the 

 blood during lead poisoning and in acute and chronic toxi-infectious 

 conditions. Protoporphyrinemia of essential hypochromic anaemia 

 (iron-deficiency anaemia) was observed and described by G. E. 

 Cartwright and his collaborators 12 , and that of infective anaemia 

 by C. J. Watson et al lz . In these cases the iron is probably prevented 

 from participating in the synthesis of haemoglobin, partly by a toxic 

 inhibition of the bone marrow and partly by a decrease in the iron, 

 which cannot be transported owing to a low and altered protein 

 content of the blood serum and which has been deposited in certain 

 tissues by the inflammatory process. In these cases the sideremia is 

 low ; in lead poisoning where inhibition of the employment of iron 

 is accompanied by an increased haemolysis, the concentration of 

 non-haemoglobin iron remains high even when that of haemoglobin 

 decreases considerably. 



These few experiments seem to show that in lead poisoning the 

 iron cannot enter into the porphyrin ring of haemoglobin. This 

 inhibition is localized in the bone marrow, and particularly in the 

 cytoplasm of the erythroblast. On the other hand lead is not able 

 to disturb the synthesis of the haem of cytochrome C. 



This observation shows us with certainty that the mechanism and 

 site of haem synthesis are different for haemoglobin and for the 

 cellular haems. The organism can lose haemoglobin very rapidly, 

 but it loses the cellular haems much more slowly and more rarely, 

 and only in particular pathological circumstances. These should 

 properly be regarded as cases of ' tissue anaemia '. 



Increase of protoporphyrin in the blood results from an inhibition 

 of haemoglobin synthesis, either by the toxic action of lead, or by 

 toxi-infectious disturbances of haemoglobin synthesis, or by iron- 

 deficiency anaemia. There are certain functional relationships between 

 the concentration of haemoglobin and that of the cellular haems, 

 governed by the respiratory necessities of the cell. 



Received July 1948 



REFERENCES 



1 Vigliani, E. and Waldenstrom, J. Dsch. Arch. Klin. Med. 18 (1937) 182 



2 Vannotti, A. and Imholz, A. Z. ges. exp. Med. 106 (1939) 597 



3 — Porphyrine und Porphyrinkrankheiten, Berlin, Springer (1937) 

 * Rimington, C. Carlsberg. Ser. chim. C.R. Lab. 22 (1938) 454 



6 Kark, R. and Meiklejohn, A. P. /. din. Invest. 21 (1942) 91 



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