Luteinizing Hormone (LH) ELISA Kits

Luteinizing hormone (LH) is a heterodimeric glycoprotein with a molecular weight of approximately 29 kDa, consisting of an α-subunit and β-subunit. The α-subunit of LH is structurally identical to that of thyroid-stimulating hormone (TSH) and follicle-stimulating hormone (FSH), whereas the β-subunit is unique to LH. LH is present in all vertebrate species, from fish to mammals, and LH-like substances have also been reported in the testes.

LH is synthesized and stored in basophilic gonadotrophs of the anterior pituitary (adenohypophysis), together with FSH. Its secretion is stimulated by gonadotropin-releasing hormone (also known as LHRH), a hypothalamic hormone. In rats, pituitary LH content is higher in males (6-7 μg/gland) than in females (3-4 μg/gland, expressed in NIH-LH1 S1 equivalents) with female levels fluctuating according to the estrous cycle.

In females, LH primarily targets mature granulosa cells in ovarian follicles. Acting synergistically with FSH, LH promotes follicular maturation and estrogen production, triggers ovulation, and, after luteinization of the follicle, stimulates the production and secretion of progesterone. In males, LH acts on interstitial (Leydig) cells in the testes to stimulate androgen production and secretion, thereby supporting spermatogenesis through the action of androgens. LH deficiency leads to reduced secretion of sex steroid hormones, atrophy of interstitial cells, and inhibition of ovulation and luteinization. Conversely, excessive LH can cause hypertrophy of interstitial cells followed by atrophy, increased secretion of estrogens and androgens, precocious ovulation, and accelerated sexual maturation. During the proestrus phase, elevated estrogen secretion induces a positive feedback mechanism that, via LHRH, triggers a transient increase in LH secretion (the so-called LH surge), leading to ovulation. LH secretion is negatively regulated by increased circulating sex steroid hormones, opioid peptides (especially β-endorphin), and physiological states such as infancy, early childhood, pregnancy, and the postpartum period.

The LBIS™ Rat LH ELISA Kit is a sandwich ELISA kit designed for the quantitative determination of luteinizing hormone (LH) in rat samples. It utilizes monoclonal antibodies specific to rat LH. All reagents are supplied in liquid form and are ready to use.

Kit Performance

Assay target	Luteinizing hormone (LH)
Calibration curve range	0.313-10 ng/mL
Analysis sample	Rat Serum/Plasma (EDTA)
Sample volume	10 μL
Measurement duration	Approx. 3 hours 50 minutes
Wavelength	Primary wavelength 450 nm Reference wavelength 620 nm

Example of Calibration Curve

Example: Measurement of LH in mouse/rat serum