36 T. F. Gallagher 



Jones and Cilento, 1949). This permitted the quaUtative 

 detection of the deuterium steroid metaboUtes without loss 

 of material. It was found that five compounds contained 

 appreciable quantities of the isotope; in the order of elution 

 from the column these were androst-2-en-17-one, androst-5- 

 ene-3:17-dione, 8etiocholane-3:17-dione, androsterone and 

 setiocholanolone. It was known from prior studies that 

 androsterone and aetiocholanolone constituted the principal 

 end products from the quantitative standpoint and these 

 substances were therefore examined in detail. Several eluates 

 contained essentially pure androsterone, using the infra-red 

 spectrum as a guide to purity. Several other eluates con- 

 tained essentially pure setiocholanolone by the same criterion. 

 The spectroscopically homogeneous androsterone fractions 

 were combined and freed from a minor non-steroid contami- 

 nant by sublimation in high vacuum. The weight of material 

 obtained in the sublimate (9'0 mg.) was in precise agreement 

 with the colorimetric determination of its 17-ketosteroid 

 content by the method of Callow (Callow, Callow and Emmens, 

 1938). The amount was therefore taken as the weight of 

 androsterone removed from the total amount excreted in the 

 urine. Although the sample removed was almost analytically 

 pure androsterone by the usual criteria, it was repeatedly 

 recrystallized until its physical constants were those of the 

 purest compound reported in the literature. A sample was 

 then analysed and from the values obtained (2 • 06 atoms per 

 cent excess deuterium in the androsterone, 2-82 atoms per 

 cent excess deuterium in the injected testosterone) it was 

 calculated that 78-4 per cent of the androsterone had been 

 made from the testosterone administered. Similar treatment 

 of the setiocholanolone fraction yielded a pure product con- 

 taining 1 • 95 atoms per cent excess deuterium, from which it 

 was calculated that 74 • 1 per cent of the excreted aitiocholano- 

 lone had its origin in the testosterone injected. 



It remained therefore to determine the total amount of 

 androsterone in the urine by application of the principle of 

 isotopic dilution. All the fractions from the chromatogram 



