luteinizing hormone in androgen production

Last reviewed 01/2018

LH acts on interstitial Leydig cells to increase the flux generating step of cholesterol conversion to pregnenolone and thence testosterone.

LH secretion is dependent upon:

  • GnRH released from the hypothalamus
  • negative feedback from testosterone on:
    • the anterior pituitary gonadodotrophin-synthesizing cells
    • the hypothalamic GnRH-releasing cells

The feedback loops are used therapeutically in advanced androgen-sensitive prostatic carcinoma:

  • GnRH analogues e.g. buserelin:
    • these are given in high dose, eventually resulting in down-regulation of GnRH receptors on pituitary gonadotroph cells
    • LH and FSH secretion is secondarily reduced
    • testosterone secretion is reduced secondary to gonadotroph reduction
  • testosterone antagonists e.g. cyproterone:
    • limits initial stimulation of prostate by GnRH analogues
    • cyproterone also acts centrally to inhibit GnRH secretion