Steroids and Bone Maturation in Infant Mice: Relative Activities of Dehydroepiandrosterone and Testosterone*

Abstract

A procedure for biological assay of the bone maturation effects of steroids, using immature mice in a 6-day test is described. Equal degrees of acceleration of bone development were produced by dehydroepiandrosterone (DHA) and testosterone with doses in a ratio of 2.4 to 1; i.e., DHA had 42 % of the potency of testosterone, with 95 % confidence limits of 20 to 84 %. In contrast, 11β-hydroxy-Δ⁴-androstenedione at its LD₅₀ had about 2 % of the potency of testosterone. Ovariectomy did not prevent the manifestation of the bone response to DHA. Corticosterone interfered with bone maturation at doses which gave a marked reduction in body growth. When a similar reduction was produced by restricting nursing time, an even greater interference with bone maturation resulted. Deoxycorticosterone was inactive in doses which give excellent maintenance of adrenalectomized mice. The sulfate of DHA was much less active than the free steroid.