Author:
Ankarberg-Lindgren C,Norjavaara E
Abstract
OBJECTIVE: To establish levels for comparison for 24-h total and free serum testosterone in prepubertal boys and throughout pubertal development. DESIGN: The study subjects were 55 healthy boys, aged 5.0-18.6 years, who underwent serial sampling one or more times during their pubertal development. METHODS: Testicular volumes were determined by orchidometer. Serum testosterone was measured by a modified RIA (detection limit, 0.03 nmol/l). Free testosterone was calculated (calc-FT) using a formula derived from the law of mass action. RESULTS: Significant increases in testosterone and calc-FT concentrations in boys were found between testis volumes of 1 ml to 2 ml, 2 ml to 3 ml, 6 ml to 8 ml, and 10 ml to 15 ml. No differences were found between testis volumes of 3, 4, 5 and 6 ml neither were there differences between 8 and 10 ml, or between 15, 20 and 25 ml. Boys who had reached their final height had higher calc-FT values than boys who had the same pubertal development but had not reached their final height. Based on the results, puberty was classified into six stages: pre1 (testis, 1 ml), pre2 (testis, 2 ml), early (testis, 3-6 ml), mid (testis, 8-12 ml), late1 (testis,15-25 ml, not reached final height) and late2 (testis, 15-25 ml, reached final height). Serum testosterone was secreted with a diurnal variation in prepuberty and during puberty. The increase of testosterone in the morning hours started earlier in pubertal than in pre-pubertal boys. The most pronounced diurnal rhythm was found in early and in mid puberty. CONCLUSION: Using a sensitive method, and a pubertal reclassification, we have established levels for comparison of testosterone and calc-FT in prepubertal and pubertal boys. The existence of data for comparison forms the basis for future studies on pubertal disorders.
Subject
Endocrinology,General Medicine,Endocrinology, Diabetes and Metabolism
Cited by
80 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献