GENERAL DISCUSSION 



Richet: Dr. Thaysen, mercury poisoning is supposed to inhibit 

 some enzymic actions and possibly reabsorption by tubular cells. I 

 should like to know something about the secretion of sweat during 

 mercury poisoning and whether you found any differences due to that 

 substance? 



Thaysen: I have not done any experiments of this kind myself, 

 but studies on mercurial diuretics have been performed, not on the 

 sweat glands but on the salivary glands, by White and co-workers 

 (1955. J. din. Invest., 34, 246). White showed that there was no 

 significant effect of mercurial diuretics on salivary sodium, potassium 

 or chloride excretion. 



Richet: Dr. Desaulles has reminded me that during chronic 

 mercuric poisoning, acrodynia for instance, there is an increase in 

 sweating. 



Thaysen: That might be due to a cerebral effect of chronic mer- 

 cury poisoning rather than to a local effect of the mercury directly 

 on the glands. 



Davson: It is rather a fortunate accident that the mercurials are 

 diuretics and that they have that specific action on the kidney 

 tubules. If you were to try and raise the mercury concentration in 

 the blood so as to put some specific mechanism apart from the kidney 

 out of action, you would kill the person anyway, because mercury 

 would interfere with so many other metabolic reactions if you really 

 could get a reasonable blood level of it for any length of time. So I 

 think investigation of it is out of the question. 



Hingerty: Is there any evidence that plasma magnesium goes up 

 at the same time as plasma potassium? In hypersecretion of aldo- 

 sterone, plasma magnesium has been reported as being decreased in 

 a few cases. We found some years ago (Conway, E. J., and Hingerty, 

 D. J. (1946). Biochem. J., 40, 561) that when plasma potassium went 

 up in adrenalectomized rats it was accompanied by an almost 

 parallel increase in the plasma magnesium ; cellular magnesium also 

 went up but rather less. 



Richet: We have made determinations of plasma magnesium in 

 more than 200 patients during acute and chronic renal failure. 

 During acute renal failure there is always an increase in plasma 

 magnesium concentration. Our technique with yellow titanium gives 

 normal values of 1 • 5 -1 • 7 m-equiv./l. In acute renal failure we some- 

 times get 3 -0-3 -5 m-equiv./l. serum magnesium. In contrast, serum 



U9 



