Gonadorelin — wholesale 10-vial kits

Research context

Gonadorelin is synthetic native gonadotropin-releasing hormone, the decapeptide pGlu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH2, also indexed as GnRH, LHRH and luliberin. The structure was determined in 1971 by the Schally laboratory, published in Biochemical and Biophysical Research Communications as a proposed sequence and then confirmed by sequential analysis; the parallel work of Schally and Guillemin on hypothalamic releasing hormones was recognized with the 1977 Nobel Prize in Physiology or Medicine. Gonadorelin is that sequence unchanged, which is what makes it the reference point for every agonist and antagonist analog — leuprolide, triptorelin, goserelin, cetrorelix, ganirelix, degarelix.

Two terminal modifications are native to the hormone, not design additions. The N-terminal pyroglutamate is a cyclized glutamate with no free alpha-amino group, so Edman sequencing is blocked and LC-MS is the practical identity method. The C-terminal glycinamide is required for receptor activation; the free-acid form is substantially less active. Between them sit the residues that analog chemistry targets: Gly6, whose replacement with a D-amino acid is the standard way to slow degradation and raise potency in agonist analogs, and the C-terminal Pro-Gly-NH2, which several analogs replace with an ethylamide. Understanding gonadorelin as the unmodified parent is the point of keeping it in a reference set.

At the molecular level gonadorelin is the endogenous agonist of the type I GnRH receptor, a class A G-protein-coupled receptor on pituitary gonadotrophs that couples predominantly through Gq to phospholipase C, inositol-phosphate signaling and calcium mobilization, as reviewed in Endocrine Reviews in 2004. The receptor's lack of the usual C-terminal cytoplasmic tail is one reason its internalization and desensitization kinetics differ from most peptide GPCRs, and the sharp contrast between pulsatile and continuous exposure — pulses sustain gonadotropin output, continuous exposure downregulates the system — is the central phenomenon that pituitary-cell and perifusion models are built to study.

Typical bench applications are radioligand and fluorescent-ligand binding at recombinant GnRHR, inositol-phosphate and calcium-flux assays, desensitization and receptor-trafficking experiments, perifused or static pituitary-cell cultures measuring LH and FSH output against pulse frequency, structure–activity comparison of analogs, and peptidase-mapping work on hormone degradation. It is the upstream partner of kisspeptin-10 in reproductive-axis models.

Regulatory position, stated factually: gonadorelin was the active ingredient of two FDA-approved U.S. products — Factrel (gonadorelin hydrochloride, NDA 018123, originally approved September 30, 1982) and the Lutrepulse Kit (gonadorelin acetate, NDA 019687, originally approved October 10, 1989) — and Drugs@FDA lists all of their product entries as discontinued, so no FDA-approved gonadorelin product is currently marketed in the United States. WholesalePeptide.us supplies gonadorelin as a research reference standard for in-vitro, analytical and preclinical laboratory research only, not as a drug product.

The N-terminal pyroglutamate blocks Edman sequencing, so LC-MS is the practical identity check. The COA for each lot reports the observed mass against the pyroglutamyl, amidated structure, and states the salt form, which differs between the historical hydrochloride and acetate products.

Research areas

• GnRH receptor binding and desensitization
• pulsatile LH and FSH release in pituitary models
• GnRH analog structure–activity
• peptide hormone degradation pathways
• recombinant GnRHR radioligand binding and calcium-flux assays
• pituitary perifusion models of pulse-frequency coding

U.S. regulatory status of the compound (as an active ingredient): No FDA-approved gonadorelin product is currently marketed in the U.S. The material sold here is a research reference chemical, not a drug product.

Handling and storage

• Store lyophilized vials at −20 °C, sealed, protected from light and moisture.
• Let the vial equilibrate to room temperature before opening to limit condensation.
• Reconstitute in an appropriate sterile buffer or solvent according to your laboratory SOP.
• Aliquot reconstituted material and avoid repeated freeze–thaw.