Gonadorelin Technical Specification Sheet
Molecular Properties
| Parameter |
Value |
| Chemical Name |
Gonadotropin-Releasing Hormone / Luteinizing Hormone-Releasing Hormone (LHRH) |
| Amino Acid Sequence |
pGlu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH₂ |
| Molecular Formula |
C₅₅H₇₅N₁₇O₁₃ |
| Molecular Weight |
1182.31 g/mol |
| CAS Number |
33515-09-2 |
| Sequence Length |
10 amino acids (decapeptide) |
| Receptor Target |
GnRH receptor (GnRHR) on pituitary gonadotrophs |
Physical Properties
| Property |
Specification |
| Appearance |
White to off-white lyophilized powder |
| Solubility |
Soluble in water, PBS (pH 7.0-7.4), or 0.9% saline at ≥1 mg/mL |
| pH (1% solution) |
5.0 - 7.0 |
| Hygroscopicity |
Low; standard desiccated storage acceptable |
| Solution Stability |
Stable at 4°C for 7-10 days; degradation at room temperature within 24-48h |
Analytical Specifications
| Test |
Specification |
| HPLC Purity |
≥98.0% |
| Mass Spectrometry |
Confirmed [M+H]⁺ = 1182.31 ± 0.5 Da |
| Peptide Content |
≥95% (by amino acid analysis) |
| Endotoxin Level |
<1.0 EU/mg |
| Acetate Content |
≤5% |
| TFA Content |
≤0.1% |
| Water Content |
≤6% (Karl Fischer) |
Storage Parameters
| Condition |
Specification |
| Lyophilized Storage |
-20°C, desiccated |
| Lyophilized Shelf Life |
24-36 months when stored properly |
| Reconstituted Storage |
2-8°C for up to 10 days; -20°C for up to 3 months |
| Reconstitution Protocol |
Add 1.0 mL sterile water or PBS to 1 mg vial; vortex gently for 30 seconds |
| Freeze-Thaw Cycles |
Maximum 3 cycles; aliquot for single use recommended |
| Light Sensitivity |
Minimal; standard laboratory storage acceptable |
Research Dosing Reference
| Application |
Typical Dose Range |
Frequency |
Route |
| In Vitro Pituitary Cell Assays |
1-100 nM |
Acute stimulation (minutes to hours) |
Culture media |
| Small Animal Models (Rodent) |
10-100 μg/kg (10-100 nmol/kg) |
Single dose or pulsatile (every 60-90 min) |
IV, SC, IP |
| LH/FSH Stimulation Test |
25-100 μg/kg |
Single bolus |
IV or SC |
| Reproductive Axis Studies |
0.1-10 μg/animal |
Pulsatile every 1-2 hours |
IV infusion pump or bolus |
Note: Dosing information is for research reference only. Gonadorelin is intended strictly for in vitro and animal research. Pulsatile administration mimics physiological secretion pattern.
Key Research Studies
| Year |
Study Focus |
Key Findings |
| 1971 |
Discovery and characterization |
First isolation and sequencing of GnRH from porcine and ovine hypothalami; demonstrated decapeptide structure with pGlu N-terminus and Gly-NH₂ C-terminus critical for activity |
| 1982 |
Pulsatile secretion pattern and receptor dynamics |
Established that pulsatile GnRH delivery (60-90 min intervals) maintains gonadotropin secretion while continuous administration causes receptor desensitization and downregulation within 7-14 days |
| 1997 |
Structure-activity relationship |
Systematic amino acid substitutions revealed positions 1, 2, 3, 6, and 10 essential for receptor binding; modifications at positions 6 and 10 generated superagonists with 50-200x potency |
| 2008 |
GnRH receptor signaling cascades |
Detailed GnRHR signaling via Gq/11 → PKC activation → Ca²⁺ mobilization → ERK1/2 phosphorylation pathway; demonstrated EC₅₀ of 0.5-2 nM for LH secretion from primary pituitary cells |
Mechanism of Action
| Biological Pathway |
Description |
| Receptor Binding |
Binds GnRH receptor (GnRHR), a Gq-coupled GPCR on anterior pituitary gonadotrophs; high affinity with Kd ~1-5 nM |
| Signal Transduction |
Activates phospholipase C → IP₃/DAG production → intracellular Ca²⁺ release → protein kinase C activation |
| Gonadotropin Secretion |
Stimulates rapid release of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) from gonadotrophs within 5-15 minutes |
| Pulsatile Requirement |
Physiological pulses every 60-120 minutes maintain LH/FSH; continuous exposure desensitizes receptors and suppresses gonadotropin output |
| Half-Life |
2-4 minutes (IV); rapid degradation by hypothalamic and pituitary peptidases |
Clinical Variants and Analogs
| Type |
Examples |
Key Modification |
| Native GnRH |
Gonadorelin acetate |
Natural sequence; short half-life |
| Superagonists |
Triptorelin, Leuprolide, Goserelin |
Position 6 and 10 substitutions; extended half-life and potency |
| Antagonists |
Cetrorelix, Ganirelix, Degarelix |
Multiple D-amino acid substitutions; competitive receptor blockade |
| Diagnostic Forms |
Gonadorelin hydrochloride |
Alternative salt form for injection; equivalent activity |
Quality Control Parameters
| Test Method |
Acceptance Criteria |
| Appearance (visual) |
White to off-white powder; no aggregation or discoloration |
| Reconstitution Test |
Complete dissolution within 1 minute; clear colorless solution |
| RP-HPLC (purity) |
Main peak ≥98.0%; no single impurity >0.5% |
| ESI-MS (identity) |
Observed [M+H]⁺ within ±0.05% of theoretical 1182.31 Da |
| Peptide Sequence Confirmation |
N-terminal pGlu and C-terminal Gly-NH₂ verified by MS/MS |
Disclaimer: This product is intended for research use only. Not for human or veterinary diagnostic or therapeutic use. Handle according to institutional biosafety protocols.