Gonadorelin
aka GnRH
Mechanism
Gonadorelin is a synthetic decapeptide identical to endogenous gonadotropin-releasing hormone (GnRH/LHRH; sequence pyroGlu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH2). It was historically FDA-approved as Factrel (diagnostic GnRH stimulation test) and Lutrepulse (pulsatile IV pump for hypothalamic amenorrhea); both products are discontinued in the US. Gonadorelin remains on the FDA Category 1 bulk substances list and is widely compounded, most commonly as an off-label adjunct to TRT intended to preserve HPG-axis signaling.
Identification
| CAS number | 33515-09-2 |
|---|---|
| Molecular formula | C55H75N17O13 |
| Sequence | QHWSYGLRPG |
| Typical dose | 100–250 mcg subcutaneous, 2–3x weekly (research use); 5–20 mcg/pulse every 90–120 min via pulsatile infusion pump for hypogonadotropic hypogonadism |
| Half-life | Distribution: 2–10 minutes; terminal: 10–40 minutes |
Vendors selling Gonadorelin
| Vendor | Size | Price | Listed purity | Trust |
|---|---|---|---|---|
| Peptide Tech | 2 mg | $29.99 | — | 94 |
| Peptidology | 5 mg | $39.99 | — | 89 |
| Peptidology | 11 mg | $39.99 | — | 89 |
| Qihang Peptide | — | — | — | 87 |
| Peptidegurus | 10 mg | — | — | 84 |
| Crystal Peptides | 5 mg | $49.00 | — | 66 |
| Peptiatlas | — | — | — | 51 |
| HongDa Peptide | — | $34.00 | — | 43 |
| zztai Peptide Ltd | 2 mg | $31.00 | — | 43 |
| zztai Peptide Ltd | 5 mg | $75.00 | — | 43 |
| zztai Peptide Ltd | 10 mg | $105.00 | — | 43 |
| MJT peptides | 2 mg | $38.00 | — | 39 |
| Kimera Chems | — | $31.99 | — | — |
| Biotech Peptides | 10 mg | $79.00 | — | — |
| Core Peptides | 10 mg | $90.00 | — | — |
| Genetic Peptide | 2 mg | $20.00 | — | — |
| Genetic Peptide | 10 mg | $20.00 | — | — |
| Modern Research Peptides | 5 mg | $32.99 | — | — |
| Oasis Labs | 10 mg | $84.00 | — | — |
| Paramount Peptides | 10 mg | $65.45 | — | — |
| Soma Peptides | 2 mg | $59.00 | — | — |
Research
The limited availability of gonadorelin has resulted in an increased use of subcutaneous triptorelin to diagnose central precocious puberty; however, studies validating its diagnostic value remain limited.
source →The aim of this study was to evaluate the effects of administering 325 mg of recombinant bovine somatotropin (rbST) at the initiation of the synchronization protocol (SYNCd) and/or on the day of embryo transfer (ETd) using a 2 × 2 experimental arrangement in Holstein heifer recipients.
source →The objective of this study was to evaluate the effect of administering 200 µg versus 100 µg of GnRH as gonadorelin hydrochloride (Factrel; Zoetis, Parsippany, NJ) at the first GnRH injection (G1) of the breeding Ovsynch in a Double-Ovsynch (DO) protocol on pregnancy per artificial insemination (P/AI) at first service…
source →Parental care enhances offspring survival but requires profound alteration of parental physiological and behavioural states.
source →The aim of this study was to compare pregnancy per AI (P/AI) in resynchronization (Resynch) protocols using different hormonal combinations (estradiol benzoate [EB], a double dose of GnRH, or EB with a double dose of GnRH) administered on the day of progesterone (P4) device insertion.
source →Queens are induced ovulators, and ovulatory success varies with hormonal status and stress.
source →Repeat-breeder cows (defined as having > 3 inseminations) significantly impact dairy profitability worldwide.
source →The objective was to evaluate the fertility of Bos indicus cows submitted to an ovulation synchronization protocol without estrogen (E2). In experiment 1, injectable P4 (P4i) was administered 10 days (D-10) before the TAI protocol.
source →Graphical abstract Abstract Central precocious puberty (CPP) results from premature activation of the hypothalamic-pituitary-gonadal axis. The GnRH stimulation test remains the diagnostic gold standard, especially in girls with undetectable basal LH levels. However, native GnRH is expensive and often unavailable.
source →Fixed-time artificial insemination (FTAI) is currently a standardized protocol for pig reproductive management. Efficient ovulation synchronization induced by GnRH analogs is critical for ensuring the pregnancy outcomes of FTAI.
source →In tambaqui (Colossoma macropomum), a rheophilic Amazonian fish of significant aquaculture importance that typically fails to spawn under captive conditions, gonadorelin has demonstrated potential in inducing ovulation and enabling strip spawning.
source →This phase III trial compares less intense hormone therapy and radiation therapy to usual hormone therapy and radiation therapy in treating patients with high risk prostate cancer and low gene risk score.
source →Ovarian reserve defines the quantity and quality of the ovarian primordial follicular pool. Diminished ovarian reserve (DOR) indicates a reduction in the quantity of ovarian follicular pool to less than expected for age. It is an important cause of infertility in many couples.
source →This is a prospective phase II study to assess the efficacy and toxicity of HSV-tk+ valacyclovir gene therapy in combination with androgen deprivation therapy, brachytherapy, external beam radiotherapy, and prostatectomy in previously untreated high-risk prostate cancer.
source →The purpose of this study is to 1) determine how hypothalamic-pituitary-adrenal axis (HPA axis) activation occurs with sleep restriction 2) evaluate how hypothalamic-pituitary-gonadal axis (HPG axis) deactivation occurs with sleep restriction.
source →This trial will assess the efficacy and safety of PGL4001 versus GnRH agonist, over a 3-month period for the pre-operative treatment of pre-menopausal women suffering from excessive uterine bleeding due to uterine myoma.
source →Fibroids are present in up to 80% of women of reproductive age. Associated heavy menstrual bleeding is often an indication for surgery. At present there are no long-term medical treatments for fibroids.
source →The purpose of this study is to compare the efficacy of two controlled ovarian stimulation protocols, the GnRH agonist protocol, widely known as the "long" protocol, and the flexible GnRH antagonist protocol, in terms of pregnancy rates and embryological data, in infertile patients receiving IVF treatment.
source →The primary purpose of this study is to evaluate the effect of the two different protocols (long protocol vs antagonist protocol) on oocyte / embryo quality.
source →