Hormone · Synthetic competitive gonadotrophin-releasing hormone receptor antagonist
Acyline
Also known as —
A GnRH decapeptide antagonist with modified aromatic residues, used to investigate receptor competition and endocrine signalling.
- Length
- 10 amino acids
- Half-life
- Not well characterised
- Mechanism
- Acyline competitively antagonises GnRHR, limiting GnRH-induced phospholipase C activation, calcium mobilisation and gonadotroph secretory signalling. Receptor blockade occurs without requiring an initial agonist response.
- Studied in
- Acyline is investigated in GnRHR binding and signalling assays, pituitary preparations and animal models of hypothalamic–pituitary–gonadal feedback.
About Acyline
Acyline is a synthetic GnRH antagonist with a ten-residue backbone, an N-acetyl group and a C-terminal amide. It incorporates several D-amino acids and non-proteinogenic aromatic residues, including acetylated aminophenylalanine derivatives at positions 5 and 6. Position 6 has D stereochemistry, while position 8 contains an isopropyl-substituted lysine. The molecule arose from analogue programmes exploring how coordinated residue substitutions could preserve GnRH receptor affinity while eliminating agonist signalling.
In laboratory systems, acyline is used to separate GnRH-dependent signalling from other inputs controlling gonadotroph function. Recombinant receptor assays offer defined binding and second-messenger measurements, whereas pituitary preparations retain more of the native secretory machinery. Animal endocrine models further incorporate steroid feedback and temporal variation in hormone release. Binding affinity and functional inhibitory potency should be reported separately, since receptor density, competing agonist concentration and assay equilibration can produce different numerical estimates.
Laboratory notes
- Confirm the specified aromatic substitutions, terminal modifications and counterion from batch documentation before comparing materials.
- Check solubility and recovery in the final assay matrix; visible clarity alone does not establish quantitative peptide recovery.
- Standardise antagonist pre-incubation and agonist challenge timing, and include receptor-negative or pathway-specific controls where feasible.
Storage and reconstitution basics: storage guide.
Questions about Acyline
How does acyline differ structurally from antide?
A key difference is at positions 5 and 6: acyline contains acetylated aminophenylalanine derivatives, whereas antide contains nicotinoyl-modified lysine residues.
Why can binding affinity and inhibitory potency differ?
Binding assays measure receptor occupancy under defined conditions. Functional assays additionally depend on agonist concentration, receptor reserve, signalling amplification and the timing of measurements.
Can acyline identify a GnRH-dependent component of a response?
Inhibition by acyline can support that interpretation when paired with suitable controls. Receptor expression, cell viability and unrelated signalling responses should also be checked before assigning pathway specificity.
Is Acyline for human use?
No. It is supplied strictly for in-vitro laboratory research and is not for human or animal consumption.
Related research peptides
All products are sold for laboratory research use only. Not for human consumption, not a medicine, not for diagnosing, treating or preventing any condition.