412 CELLS, TISSUES, AND ORGANISMS 



TABLE II 



Mean Urinary Estrogen Outputs 

 in Normal Male Subjects of Various Ages 

 (Age Range and Numbers as in Table 1) 



TABLE III 



The Output Ratios of Various Urinary Steroids 



in Men of Various Ages 



( Age Range and Numbers as in Table 1 ) 



Calculated change 



from age 30 



to age 70 -45.6% -7.7% +12.6% 



estriol output rise is here a slow decline. Over-all estrogen excretion 

 therefore declines at a rate of about 7.5 per cent per decade. 



To ascertain if there are any indications of an age-related altera- 

 tion in metabolism, we have determined the ratios of metabolically 

 inter-related compounds (Table III). These data suggest: (1) that the 

 metabolism of the estrogens through pathways leading to estriol pro- 

 duction is increasingly favored with advancing years; (2) that there is 

 a slight but probably not significant tendency for 11-deoxy-steroids to 

 be metabolized to the 5/? isomer; ( 3 ) that the proportion of 5a isomers 



