Glossary
Peptide research terms, plainly defined.
A reference for the vocabulary that turns up across reviews, comparisons and guides — mechanism, research method, regulatory classification, and quality signals.
- Entries
- 60
- Last Updated
- May 2026
Mechanism
GLP-1 receptor agonist
A compound that activates the GLP-1 receptor, a protein found on cells throughout the body that responds to blood glucose levels.
Read definitionGHRH analog
A synthetic molecule that mimics growth hormone-releasing hormone and stimulates the pituitary gland to release growth hormone.
Read definitionGH secretagogue
Any compound that stimulates the release of growth hormone, encompassing peptide and non-peptide molecules that act through various mechanisms.
Read definitionMelanocortin receptor
A family of cell-surface proteins that bind melanocyte-stimulating hormones and regulate pigmentation, appetite, and immune function.
Read definitionGhrelin receptor
A G-protein-coupled receptor activated by ghrelin, an appetite-stimulating hormone produced primarily in the stomach.
Read definitionIncretin
A hormone secreted by the intestines in response to glucose intake that enhances insulin secretion from pancreatic beta cells.
Read definitionPeptide hormone
A hormone composed of amino acids that acts as a signaling molecule to regulate physiological processes throughout the body.
Read definitionAgonist vs antagonist
An agonist activates a receptor; an antagonist blocks it — a fundamental distinction in how compounds interact with cellular targets.
Read definitionReceptor binding
The interaction between a ligand (such as a peptide) and a cellular receptor protein, the first step in initiating a biological response.
Read definitionSignal transduction
The cascade of molecular events inside a cell triggered by receptor binding, converting an external signal into a cellular response.
Read definitionSecond messenger
An intracellular signaling molecule that relays signals from receptors on the cell surface to target molecules in the cell.
Read definitionDose-response curve
A graph showing how a biological effect changes with increasing doses of a compound, essential for determining efficacy and safety.
Read definitionResearch
Preclinical research
Laboratory and animal studies conducted before human trials to establish safety, efficacy, and mechanism of action of a compound.
Read definitionRandomised controlled trial (RCT)
A study design in which participants are randomly assigned to receive a test treatment or control, minimizing bias in treatment allocation.
Read definitionMeta-analysis
A statistical technique that combines results from multiple independent studies to derive an overall estimate of effect size and evidence quality.
Read definitionSample size
The number of participants enrolled in a study, determined by statistical calculations to ensure sufficient power to detect meaningful treatment effects.
Read definitionMechanism of action (MoA)
The specific biochemical or physiological process by which a compound produces its biological effects at the molecular and cellular level.
Read definitionIn vitro
Research conducted in a test tube or laboratory dish using isolated cells or tissue, outside a living organism.
Read definitionIn vivo
Research conducted in a living organism (animal or human), studying how compounds behave in complex biological systems.
Read definitionDouble-blind study
A research design where neither participants nor researchers know which treatment each participant receives, preventing bias in results.
Read definitionPlacebo control
A comparison group receiving an inert substance in place of the active treatment, allowing researchers to distinguish true drug effects from placebo responses.
Read definitionPrimary endpoint
The main outcome measure that a research study is designed to evaluate, specified before the study begins.
Read definitionSecondary endpoint
Additional outcome measures in a research study that provide supporting evidence but are not the main focus of evaluation.
Read definitionRegulation
TGA (Therapeutic Goods Administration)
Australia's federal regulatory body responsible for evaluating and approving therapeutic goods, including medicines and biological products.
Read definitionARTG (Australian Register of Therapeutic Goods)
Australia's public database of all approved therapeutic goods, detailing registration status, approved indications, dose, and restrictions.
Read definitionSchedule 4 medicine
In Australia, a prescription-only medicine that can only be dispensed by a pharmacist on the order of a medical practitioner.
Read definitionWADA prohibited list
The World Anti-Doping Agency's annual list of substances and methods banned in sport due to their performance-enhancing potential or health risks.
Read definitionSpecial Access Scheme (SAS)
An Australian regulatory pathway that allows medical practitioners to obtain unapproved therapeutic goods for individual patients with serious medical conditions.
Read definitionResearch use only
A designation indicating that a compound is intended solely for scientific investigation and not approved for human consumption or therapeutic use.
Read definitionPharmacist-only medicine (POM)
A therapeutic good in Australia that can only be supplied by a registered pharmacist, without requiring a doctor's prescription.
Read definitionOff-label use
The prescribing of an approved therapeutic good for a condition, dose, or population not included in the approved product information.
Read definitionCompounding pharmacy
A pharmacy that prepares customized medicines by combining or modifying pharmaceutical ingredients according to a prescriber's instructions.
Read definitionMIMS (Monthly Index of Medical Specialties)
An Australian database and resource that lists therapeutic goods registered with the TGA, including approved indications, dosing, and safety information.
Read definitionAHPRA (Australian Health Practitioner Regulation Agency)
Australia's regulatory authority that registers and regulates health practitioners and investigates complaints about professional conduct.
Read definitionQuality
Certificate of Analysis (COA)
A document from a testing laboratory certifying the identity, purity, potency, and other quality parameters of a chemical or biological compound.
Read definitionHigh-performance liquid chromatography (HPLC)
An analytical technique that separates chemical compounds in a mixture for identification and quantification of purity and composition.
Read definitionMass spectrometry (MS)
An analytical technique that measures the mass-to-charge ratio of molecules to determine chemical composition, structure, and purity.
Read definitionThird-party testing
Quality testing performed by an independent laboratory unaffiliated with the manufacturer to provide objective verification of product composition and purity.
Read definitionEndotoxin testing
Quality testing that detects bacterial lipopolysaccharide (endotoxin) contamination, a pyrogen that can trigger fever and immune responses when introduced to the body.
Read definitionBatch number
A unique identifier assigned to a specific production lot of a pharmaceutical or chemical compound, used for traceability and quality tracking.
Read definitionLiquid chromatography (LC)
An analytical technique that separates and measures individual compounds in a mixture based on their chemical properties, essential for assessing peptide purity.
Read definitionRetention time
The time it takes for a compound to travel through a chromatography column, used to identify and characterize peptides in quality testing.
Read definitionPeak area
The area under a peak in a chromatogram, quantitatively proportional to the amount of a compound in a sample.
Read definitionContaminant profile
A characterization of the impurities and unwanted compounds present in a peptide sample, critical for assessing safety and quality.
Read definitionSterile filtration
A process using specialized filters to remove microorganisms from solutions, ensuring safety for injectable peptide preparations.
Read definitionPharmacology
Half-life
The time required for the concentration of a compound in the body to decline to 50% of its initial level, determining how frequently dosing is needed.
Read definitionBioavailability
The extent and rate at which a compound reaches systemic circulation and becomes available to target tissues after administration.
Read definitionPeptide bond
A covalent chemical linkage formed between amino acids in which the carboxyl group of one amino acid reacts with the amino group of the next.
Read definitionPharmacokinetics (PK)
The study of how the body absorbs, distributes, metabolizes, and excretes a compound, determining its concentration in the body over time.
Read definitionReceptor downregulation
A reduction in the number or sensitivity of receptors on cells, often occurring with prolonged exposure to agonists.
Read definitionTachyphylaxis
Rapid development of tolerance to a compound, occurring over minutes to hours, reducing the effectiveness of repeated or continuous doses.
Read definitionArea under the curve (AUC)
A pharmacokinetic parameter that quantifies the total drug exposure over time, calculated from a plasma concentration-time graph.
Read definitionCmax (maximum concentration)
The highest concentration of a drug in the bloodstream after a single dose, indicating peak exposure and efficacy.
Read definitionClinical
Adverse event (AE)
Any undesirable medical occurrence in a research participant, whether or not considered related to the investigational compound.
Read definitionLipodystrophy
An abnormal distribution or loss of body fat, which can occur as a side effect in some research or clinical contexts and may affect metabolic health.
Read definitionIGF-1 (Insulin-like growth factor 1)
A hormone produced primarily by the liver in response to growth hormone stimulation, crucial for growth, metabolism, and cellular survival.
Read definitionAdverse drug reaction (ADR)
An unintended harmful effect produced by a drug at normal doses, distinct from accidental overdose or misuse.
Read definitionContraindication
A medical condition or circumstance that makes a particular treatment inappropriate or dangerous for a specific patient.
Read definitionDose-limiting toxicity (DLT)
The highest dose of a drug that produces an unacceptable level of adverse effects, beyond which dose escalation cannot proceed.
Read definitionBiomarker
A measurable biological characteristic (substance, molecule, or gene) that indicates disease status, treatment response, or risk of future disease.
Read definition