Pituitary-gonadal relations in male children and adolescents

Abstract

10 μg/100 ml) were achieved by age 8, and levels reached a plateau by age 15 (Fig. 6). Adult LH levels (>2.5 μg/100 ml) were reached by age 13 and a plateau was observed after 17 years. Plasma testosterone also ceased to rise after age 17. The data suggest that the testis may undergo progressive gonadotropin-mediated maturation in late childhood. Testosterone secretion by the Leydig cells at puberty may result from a further rise in LH levels. Speculation: ituitary secretion of gonadotropins, particularly FSH, in male children is a gradual phenomenon, antedating by several years the release of testosterone by the testis. This gradual rise may represent a progressive reduction in hypothalamic sensitivity to feedback by testicular steroids other than testosterone. In late childhood, rising FSH and LH levels may induce increased activity of the enzymes responsible for both synthesis and catabolism of testosterone. At puberty, an LH-mediated reduction in reductase activity might then result in testosterone accumulation and secretion. © 1972 International Pediatric Research Foundation, Inc.