17-KETOSTEROID EXCRETION IN AGEING 

 SUBJECTS* 



Betty L. Rubin, ph.d., R. I. Dorfman, Ph.D., 



AND G. PiNCUS, D.Sc. 

 Worcester Foundation for Experimental Biology, Shreivsbury, Mass. 



Many studies of the changes in adrenal function with 

 increasing age or with disease have been based on the indices 

 of total urinary corticoid excretion and total urinary 17- 

 ketosteroid excretion. They have demonstrated a decreased 

 excretion of both classes of steroid with increasing age. How- 

 ever, these decreases are not parallel. To cite only one study, 

 that of Pincus, RomanofP and Carlo (1954), carried out at the 

 Worcester Foundation on men and women aged twenty to 

 ninety, it was found that the 17-ketosteroids decreased more 

 markedly with age than did the corticoids. 



Two recent developments have made it possible to derive 

 more information about the function of the adrenal gland in 

 aged individuals from a more detailed study of urinary 17- 

 ketosteroids. First, metabolism studies with the steroid 

 hormones have established the relationships between endo- 

 genous steroids and the individual 17-ketosteroids of the 

 urine, and secondly, methods have been developed which 

 make possible the quantitative determination of six indivi- 

 dual a- 17-ketosteroids in a urine extract containing as little 

 as 2-5 mg. of Zimmermann-reacting material. 



The metabolic relationships for which there is experimental 

 evidence are presented in Figs. 1 and 2. Fig. 1 shows what 

 we consider to be the principal pathways in the biosynthesis 

 of the biologically active adrenal steroids. Cholesterol, a Cgg 

 steroid with the 3/3-hydroxy-zl^ configuration, and other 



♦Investigations described in this paper have been supported by grant 

 number H-1659(C6) from the U.S. Pubhc Health Service. 



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