39341-83-8

Basic information

• Product Name: HLH
• Synonyms: LUTEINIZING HORMONE;LUTEINIZING HORMONE, HUMAN;LUTEINIZING HORMONE, HUMAN PITUITARY;LH;LH, HUMAN PITUITARY;ICSH;HLH;PLH
• CAS NO: 39341-83-8
• Molecular Formula: NULL
• Molecular Weight: 0
• EINECS: 254-420-6
• Mol File: 39341-83-8.mol
• Article Data: 0

Chemical Properties

• Appearance: /lyophilized powder
• Storage Temp.: 2-8°C
• CAS DataBase Reference: HLH(CAS DataBase Reference)
• NIST Chemistry Reference: HLH(39341-83-8)
• EPA Substance Registry System: HLH(39341-83-8)

Safety Data

• Hazard Codes: T,B
• Statements: 60
• Safety Statements: 53-22-36/37/39-45
• WGK Germany: 3
• RTECS: OK6367000
• Hazardous Substances Data: 39341-83-8(Hazardous Substances Data)

Usage

Description

HLH, also known as Luteinizing Hormone (LH), is a gonadotropic glycoprotein hormone secreted from the anterior pituitary. It plays a crucial role in the reproductive system of both males and females. In females, LH triggers ovulation and stimulates the development of the corpus luteum, while in males, it stimulates androgen production and spermatogenesis.

Uses

Used in Fertility Treatments:
HLH is used as a treatment for female infertility, particularly in cases where there is a need to stimulate the production of estrogens and the transformation of ovarian follicles into corpora lutea. Recombinant human LH is employed for this purpose.
Used in Infertility Treatments for Women:
HLH, in the form of menotropins (human menopausal gonadotropin, hMG), which is a mixture of FSH and LH, is used to treat infertility in women. This combination helps stimulate the development of ovarian follicles and the production of estrogens.
Used as an LH Substitute:
HLH, derived from the urine of pregnant women in the form of hCG (human chorionic gonadotropin), is used as an LH substitute. It serves the same purpose as LH in the reproductive system, particularly in stimulating the production of estrogens and the development of the corpus luteum in females.
Used in Predicting Ovulation:
A surge in LH levels is tested to predict ovulation using urinary ovulation predictor kits. This helps in identifying the most fertile days in a woman's menstrual cycle, which can be useful for family planning or infertility treatments.
Used in Drug Delivery Systems:
While not explicitly mentioned in the provided materials, it can be inferred that HLH agonists and antagonists, such as hCG and purified or recombinant human LH, may be used in drug delivery systems to enhance the efficacy of fertility treatments. These agonists and antagonists can be incorporated into various formulations to improve the delivery, bioavailability, and therapeutic outcomes of LH-based treatments.

Structure

LH is a glycoprotein consisting of noncovalently linked glycoprotein hormone (GPH) α- and LH β-subunits. The GPH α-subunit is common to folliclestimulating hormone (FSH), thyroid-stimulating hormone (TSH), and chorionic gonadotropin (CG). The LH β-subunit contains a cysteine-knot motif, which is critical for the heterodimer assembly and biological activity of the hormone. The N-linked oligosaccharide chain is important for the intracellular folding, secretion, metabolic clearance, and biological activity of the hormone.?Mr 26,000–48,000. pI: human LH, 7.2–9.2; rat LH, 8.6–9.3; pig LH, 7.2–9.2; horse LH, 4.5–7.5. Multiple isoforms exist due to the microheterogeneity of oligosaccharide chains. Soluble in water; insoluble in alcohol and acetone. Partially (50%) dissociated to two subunits at pH 1.9. Inactivated by oxidation (hydrogen peroxide, periodic acid), reduction (cysteine, ketone), and treatment with trypsin, chymotrypsin, and pepsin. Picrolonic, flavianic, picric, and trichloroacetic acids precipitate LH with retention of its activity.

Gene, mRNA, and precursor

The human LH β-subunit gene, LHB, location 2p21, consists of three exons. The human LH β-subunit mRNA has 523 b that encode a signal peptide of 20 aa residues and a mature protein of 121 aa residues.?The LH β-subunit gene is expressed in the basophilic gonadotropes in the anterior pituitary. In tetrapods, FSH and LH are coexpressed in gonadotropes, whereas they are produced in different cells in teleosts.

Receptors

The receptor of LH (LHR) is a glycoprotein that belongs to a subclass of the rhodopsin/β-adrenergic subfamily of the membrane-bound GPCR superfamily. The LHR consists of around 700 aa residues and contains a large N-terminal extracellular domain (~360 aa residues), seven transmembrane domains, and a C-terminal intracellular domain.??The receptor mainly couples to the Gs protein, and LH stimulates the production of cAMP in target cells.

Clinical implications

A single mutation (Gly 578 Asp) in the sixth transmembrane domain of LHR resulting in the constitutive activation of the LHR causes familial male precocious puberty.16 A missense mutation (Ala 593 Pro) in the sixth transmembrane domain of LHR causes Leydig cell hypoplasia. Conditions with high LH levels include premature menopause, gonadal dysgenesis, Turner syndrome, castration, Swyer syndrome, polycystic ovary syndrome, certain forms of congenital adrenal hyperplasia, testicular failure, and pregnancy. Conditions with low FSH levels include Kallmann syndrome, hypothalamic suppression, hypopituitarism, eating disorders, female athlete triad, hyperprolactinemia, and hypogonadism.

Synthesis and release

The synthesis and release of LH are regulated by GnRH, gonadotropin-inhibitory hormone (GnIH), gonadal steroids, and dopamine. In tetrapods, GnRH acts directly on gonadotropes and differentially regulates LH and FSH secretion through changes in the pattern of GnRH pulsatile secretion. GnIH inhibits LH secretion in birds and mammals, whereas GnIH can stimulate and inhibit LH secretion in fish depending on the species and reproductive status. LH secretion is regulated by gonadal steroids such as estradiol and testosterone. Gonadal steroids exert their effects at the level of the hypothalamus by changing GnRH secretion, and directly at the level of the gonadotropes, where they exert different effects depending on the species and reproductive condition of animals. In teleosts, dopamine inhibits both basal and GnRH-stimulated LH secretion.