Testosterone concentrations in human seminal plasma and saliva and its correlation with non-protein-bound and total testosterone levels in serum.
A sensitive, specific and precise non-chromatographic method for the radioimmunoassay of testosterone in human seminal plasma and saliva from adult and pubertal males is described, and the values compared to total and non-protein-bound testosterone levels in serum. There was a significant correlation between salivary and serum-free levels of testosterone (r = 0.75, P less than 0.001, n = 67) whilst the correlation of serum levels of total testosterone with free as well as with salivary testosterone levels was weaker (r = 0.63 and 0.64, respectively). The salivary and serum levels of free testosterone showed better correlation with the stage of puberty than did the serum levels of total testosterone. Further evidence for a correlation between salivary and serum levels of free testosterone was obtained following oral administration of testosterone undecanoate, as this treatment increased the mean concentration of serum total testosterone after 3 h by 82%, but increased salivary and serum levels of free testosterone by only 30% and 20%, respectively. The coefficient of correlation between serum levels of total testosterone and seminal plasma testosterone was 0.73 (P less than 0.001), whilst the correlation between levels of serum-free testosterone with both salivary and seminal plasma levels of testosterone was statistically non-significant. Our observations on salivary testosterone are in accordance with the diffusion of non-protein-bound steroids into peripheral tissues, and consequently into their secretions. This model, however, does not appear to be applicable to the sex accessory glands.
D000293:Adolescent; D000328:Adult; D001798:Blood Proteins / Q000378:metabolism; D002648:Child; D006801:Humans; D008297:Male; D008875:Middle Aged; D011485:Protein Binding; D011627:Puberty; D012463:Saliva / Q000378:metabolism*; D012661:Semen / Q000378:metabolism*; D013739:Testosterone / Q000031:analogs & derivatives / Q000032:analysis / Q000097:blood / Q000378:metabolism* / Q000494:pharmacology
D001798:Blood Proteins; D013739:Testosterone; C010792:testosterone undecanoate