ANDROGENIC ACTIVITY PER MILLIGRAM OF COLORIMETRICALLY MEASURED KETOSTEROIDS IN URINE: AN INDEX OF THE RESPECTIVE CONTRIBUTIONS FROM TESTICULAR AND EXTRA-TESTICULAR SOURCES*

Publisher Website
Google Scholar
Abstract
THE theses of this communication are that the number of international units (i.u.) of androgens per milligram of colorimetrically measured urinary ketosteroids a) reflects the relative proportions of urinary ketosteroids1 derived from testicular and extra-testicular sources and b) can be used as an index of the respective degrees of function oftesticular versus extra-testicular sources. Urinary androgenic activity in the normal human adult depends chiefly upon androsterone (Fig. 3), the bulk of which is dervied from testicular secretions in normal men (2, 3,4). Androsterone is present in large quantities in human urine (Fig. 2) and has a much higherandrogenic activity than that of any compound originating primarily from adrenocortical or other extra-testicular sources (3). In contrast to androgenic values, colorimetric assays of urinary ketosteroids are a “blanket” measurement of the total quantity of ketosteroids, without regard to their androgenic activity. Thus an index afforded by the androgenic activity per milligram of colorimetrically determined urinary ketosteroids represents a balance that in males is struck between the proportions of a) highly androgenic metabolites derived largely from testicular secretions (chiefly androsterone) and b) ketosteroids with less androgenic activity, derived chiefly from extra-testicular sources.