Description

Luteinizing hormone (LH) is produced in both men and women from the anterior pituitary gland in response to luteinizing hormone-releasing hormone (LH-RH or Gn-RH), which is released by the hypothalamus.

LH is a glycoprotein hormone having two subunits. The alpha subunit is similar to FSH, HCG and TSH. The beta subunit is different from those of the other glycoprotein hormones and confers its biochemical specificity.

In males, LH is also called interstitial cell-stimulating hormone (ICSH). In both males and females, LH secretion is regulated by a balance of positive and negative feedback mechanisms involving the hypothalamic-pituitary axis, the reproductive organs and the pituitary and sex steroid hormones. LH and the other pituitary gonadotropin, FSH, play a critical role in maintaining the normal function of the male and female reproductive systems.

Patients suffering from hypoginadism show increased concentration of serum LH. A decrease in steriod hormone production in females is a result of immature ovaries, primary ovarian failure, polycystic ovary disease or menopause. In these cases, LH secretion is not regulated. A similar loss of regulatory hormones occurs in males when the testes develop abnormally or anorchia exists. Increased concentrations of LH may be found in primary testicular failure, Klinefelter syndrome, renal failure, cirrhosis, hyperthyrodism and severe starvation.

LH is a useful marker in determining the homeostasis fertility regulation via the hypothalamic-pituitary-gonadal axis.