A COMPARISON OF THE EXCRETORY POWER OF THE SKIN WITH THAT OF THE KIDNEY THROUGH A STUDY OF HUMAN SWEAT

Abstract

The fact that the skin and the kidneys can act, to a certain extent, vicariously, seems to be generally accepted, as is manifest by the use of sweat-baths in the treatment of uremia.The skin excretes, qualitatively, practically the same substances which occur in the urine, namely, urea, ammonia, uric acid, amino-acids,1 creatinin,2 chlorids, phosphates, sul- phates and certain enzymes.3The quantity of these substances, however, excreted by the skin is, normally, far less than that eliminated through the kidneys.In health the ratio of the quantities of the various urinary constit- uents to one another is fairly constant, independent of the actual amounts of the substances eliminated by the kidney.Moreover, this ratio for urine differs from that existing between the same substances in the bl ood\x=req-\ stream.Hence the kidney exercises a selective concentrating action for certain substances.The question then suggests itself as to whether or not any such relation exists between the normal constituents of sweat, and, further, if any definite relation obtains between the quantities of the substances eliminated through the skin and kidneys.Such a similar rela- tionship of the urinary and sweat factors would tend to show a similar selective power between the skin and kidneys.Favre and later Kast4 studied the relationship between the chlorids, phosphates and sulphates in the urine and sweat.The results show no outspoken relationship between the mineral constituents of the two fluids.These investigators found the ratios shown in Table 1 between these substances in sweat and urine.Aliprando Moriggia5 has noted the similarity of substances excreted both in sweat and urine, but showed the presence of an acid sweat in experimental alkalinuria in man, while in herbívora an experimental