About LH / Luteinizing hormone:
Luteinizing hormone is also known as lutropin or lutrophin. This is a hormone that is produced by the gonadotropic cells that are found in the anterior pituitary gland. The sharp rise of Lh, known as an LH surge, is what triggers ovulation, and develops the corpus luteum.
In males, LH, also called interstitial cell-stimulating hormone (ICSH) stimulates Leydig cell production of testosterone.
LH Structure
Luteinizing hormone is a heterodimeric glycoprotein. Each monomeric unit is a glycoprotein molecule. Made of one alpha and one beta subunit, making a fully functional protein.
The structure is similar to FSH, TSH, and hCG.
The alpha subunits FSH, TSH, hCG, and LH are all identical in that they contain 92 amino acids in humans. However, that is increased slightly in all other vertebrate species. These glycoproteins don’t exist in invertebrates.
Luteinizing hormone Function
In both sexes, LH works on endocrine cells, in the gonads to produce androgens.
In females, LH supports cells in the ovaries to produce androgens and the hormonal precursors required for estradiol productions. During menstruation FSH initiated follicular growth, this impacts the granulosa cells.
In men, Lh acts on the Leydig cells in the testes and is regulated by GnRH. The Leydig cells produce testosterone controlled by LH.
LH Normal Levels
Lh levels are usually low during childhood, and they become high after women reach menopause. LH is secreted in pulses, so data has to be gathered over a reasonable amount of time to find out how much is in the blood levels. In productive years levels are between 1-20 UH/L.