title: Impaired Leydig cell reserve and altered serum androgen binding in the aging male.
abstract: The hormonal profile of the aging male reveals an associated decrease in free testosterone and 5 alpha-dihydrotestosterone (DHT) levels and increased luteinizing hormone levels. Later events consist of a decrease in total testosterone, stable DHT, and increased follicle-stimulating hormone and estradiol levels. Although most available information supports the concept of impaired Leydig cell reserve, our study suggests some degree of hypothalamic-pituitary dysfunction. The signal for increased androgen binding with age is not clear. There is a great deal of individual variation in the time of onset of these events.
mesh_terms: D000368:Aged; D000375:Aging; D013196:Dihydrotestosterone / Q000097:blood*; D004958:Estradiol / Q000097:blood; D005640:Follicle Stimulating Hormone / Q000097:blood; D006801:Humans; D007985:Leydig Cells / Q000378:metabolism*; D007986:Luteinizing Hormone / Q000097:blood*; D008297:Male; D008875:Middle Aged; D011485:Protein Binding; D013739:Testosterone / Q000097:blood*
chemical_list: D013196:Dihydrotestosterone; D013739:Testosterone; D004958:Estradiol; D007986:Luteinizing Hormone; D005640:Follicle Stimulating Hormone