- Le Laboratoire: Diagnostic, Explorations Fonctionnelles et Traitement du Sperme
- Published:
Dosage de la testostérone plasmatique chez l’homme
Plasma testosterone assay in men
Andrologie volume 4, pages 216–222 (1994)
Resume
Le principe des diverses méthodes de dosage de la testostérone et de ses formes circulantes est décrit: 1° — dosage radioimmunologique de la testostérone totale avec un traceur tritié, après extraction des stéroïdes et chromatographie (méthode de référence), 2° — méthodes de dosage directes dans le plasma, 3° — dosage de la testostérone non liée à la SBP (fraction biodisponible pour les cellules cibles), utile dans les cas de modifications de la concentration plasmatique de SBP (hyperthyroïdie, andropause, insuffisance testiculaire exocrine sévère), 4° — dosage de la testostérone libre. II existe des fluctuations épisodiques et un rythme nycthéméral de la testostéronémie, de larges variations inter-sujets et une diminution très progressive avec l’âge.
Abstract
The measurement of testosterone in plasma is the main tool to investigate the endocrine function of the testis. Radioimmunoassay of total testosterone using3H-testosterone as tracer, after steroid extraction and chromatography avoids the interactions of steroids and plasma proteins in the assay. It can be considered as a method of reference. Direct methods, without extraction and chromatography, and using non-radioactive tracers have been developped. They are easier and faster to perform but less accurate because of the aforementioned interactions. In the plasma, testosterone is mainly bound with a high affinity to SBP and with a low affinity to albumin. Non-SBP-bound testosterone is considered to represent the fraction of the testosterone available for target cells. Non-SBP-bound testosterone can be measured after precipitation of SBP by ammonium sulfate. This procedure is usefull to investigate androgenicity when plasma SBP concentrations are altered such as in hyperthyroidism, aging and severe exocrine testicular failure. Plasma free testosterone can be mesured by equilibrium dialysis, a procedure not suitable for routine assay or more easily but less accuratly by direct measurement in the plasma with methods using tracer analogs. The interpretation of testosterone measurement must take into account moment-to-moment and nycthemeral variations. The inter-subject variations of plasma testosterone concentrations are large, the decrease with aging is very progressive. Testosterone has a permisive effect on male sexual function with a threshold level above which no relationship between plasma testosterone concentration and sexual “performances” could be demonstrated. Because of the multifactorial control of human sexual function, the threshold value is difficult to determine for a given patient.
References
DE LIGNIERE B., VINCENS M.: Variations fonctionnelles de l’activité testiculaire. In: Mauvais Jarvis P., Schaison G., Bouchard P., Mahoudeau J., Labrie F. eds. Médecine de la reproduction masculine. Paris, Flammarion, Médecine Sciences, 1984: 441–447.
DÉCHAUD H., LEJEUNE H., CHOLLET M., MALLEIN R., PUGEAT M.: Radioimmunoassay of testosterone not bound to sex steroid-binding protein in plasma. Clin. Chem. 1989, 35: 1609–1614.
FOREST M.G.: Modifications hormonales et mécanismes neuroendocriniens de la puberté. In: La puberté masculine et ses pathologies. Progrès en Andrologie. Paris, Doin eds, 1993; 4: 7–23.
HUBERT W.: Psychotropic effects of testosterone. In: Nieschlag E., Behrer H.M. eds. Testosterone: action, deficiency, substitution. Berlin, Heidelberg, New York, Springer-Verlag, 1990: 51–71.
LEJEUNE H., DÉCHAUD H., PUGEAT M.: Évolution de l’axe hypothalamo-hypophyso-testiculaire au cours du vieillissement. Contracept. Fertil. Sex., 1991; 19: 951–957.
SCHAISON G., VALCKE J.C., HYPOGONA-DISMES. IN: MAUVAIS JARVIS P., SCHAISON G., BOUCHARD P., MAHOUDEAU J., LABRIE F. EDS.: Médecine de la reproduction masculine. Paris, Flammarion, Médecine Sciences, 1984: 251–290.
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Lejeune, H., Dechaud, H. Dosage de la testostérone plasmatique chez l’homme. Androl. 4, 216–222 (1994). https://doi.org/10.1007/BF03034288
Published:
Issue Date:
DOI: https://doi.org/10.1007/BF03034288
Mots clés
- Testostérone
- Sex steroid-binding protein
- testostérone biodisponible
- immunodosage
- hypogonadisme
- andropause