Reference
Glossary
The terms used across the library, defined in the sense they are used here.
503A Bulks List
The list of bulk drug substances a licensed compounding pharmacy may lawfully use for an individual patient prescription. Inclusion is not a drug approval and requires no efficacy trial — it permits compounding, nothing more.
Agonist / antagonist
An agonist activates a receptor; an antagonist blocks it. The distinction is not always the obvious one: continuous stimulation by a GnRH <em>agonist</em> desensitises the pituitary and suppresses testosterone, arriving at the same destination as an antagonist by the opposite route and with an initial hormone surge on the way.
AMPK
AMP-activated protein kinase — the cell energy sensor. Activated by low energy state and by exercise; drives glucose uptake, fatty acid oxidation and mitochondrial biogenesis. Reciprocally antagonistic with mTOR.
Anaphylaxis
A severe systemic allergic reaction, typically within minutes: widespread hives, swelling of the lips, tongue or throat, wheeze, vomiting or collapse. Treated with adrenaline into the outer thigh, not antihistamines. Any injected substance can cause it, and asthma raises the risk of a fatal outcome.
Angiogenesis
Formation of new blood vessels. The mechanism behind several repair peptides, and simultaneously the reason they carry a theoretical oncological concern.
Anti-fibrotic
Reducing formation of scar tissue. Distinct from anti-inflammatory: fibrosis is the structural end-state of repair, not the inflammatory phase.
Bacteriostatic water
Sterile water with 0.9% benzyl alcohol as a preservative, permitting repeated withdrawals from one vial. The standard diluent for multi-draw work.
BDNF
Brain-derived neurotrophic factor — a growth factor supporting neuronal survival and plasticity. The proposed substrate for most nootropic peptide claims.
Bioavailability
The fraction of an administered dose reaching the circulation intact. Most peptides have almost none by mouth, which is why they are injected — and why the exceptions are interesting.
Boxed warning
The most serious warning a regulator applies to a drug label, reserved for risks that are life-threatening or require specific monitoring. Several compounds documented here carry one, and it survives being used off-label.
Cardiolipin
The signature phospholipid of the inner mitochondrial membrane, essential for cristae curvature and respiratory supercomplex assembly. The binding target of SS-31.
COA (certificate of analysis)
A laboratory report stating identity and purity for a specific batch. Only meaningful if it is batch-specific and from an independent laboratory.
Cristae
The folded inner membrane structures of a mitochondrion. Their geometry directly determines respiratory efficiency.
DAC (drug affinity complex)
An albumin-binding modification that extends half-life dramatically. CJC-1295 with DAC lasts days; without DAC, roughly half an hour. The distinction changes the entire pharmacology.
Depot
A long-acting formulation releasing drug slowly over weeks or months from an injection site. It changes the exposure profile fundamentally: a depot produces a plateau where the same molecule given short-acting produces a pulse.
Endotoxin
Bacterial cell-wall debris that survives sterilisation and is not removed by a sterile filter. Causes fever, rigors and malaise within hours of injection. Unquantified in research-grade material, and a separate problem from whether a vial is sterile.
First-pass metabolism
Breakdown of an orally absorbed drug by the gut wall and liver before it reaches the general circulation. The reason some drugs are given sublingually or by injection.
GHRH
Growth hormone-releasing hormone. Analogues stimulate pituitary GH release upstream, preserving pulsatility and feedback control.
GHS-R1a
The growth hormone secretagogue (ghrelin) receptor. A second, separate route to pituitary GH release — which is why GHRH analogues and ghrelin mimetics are synergistic.
Grey market
Supply of unapproved compounds labelled for research use, purchased and used outside any regulatory or clinical framework. Unverified by definition.
Hayflick limit
The number of times a normal somatic cell can divide before senescence, governed by telomere shortening. A tumour-suppressive mechanism, not merely a defect of ageing.
IGF-1
Insulin-like growth factor 1 — the principal mediator of growth hormone effects, produced mainly by the liver. The practical monitoring marker for total GH exposure.
Incretin
Gut hormones (GLP-1, GIP) that amplify glucose-dependent insulin secretion. The basis of the modern metabolic drug class.
Lyophilised
Freeze-dried. Peptides are supplied this way because the solid state is dramatically more stable than solution.
MMP (matrix metalloproteinase)
Enzymes that degrade extracellular matrix. Upregulating them alongside collagen synthesis produces remodelling rather than simple deposition.
mTOR
Mechanistic target of rapamycin — the growth and protein-synthesis signalling node. Reciprocally antagonistic with AMPK, which matters when a protocol activates one while pursuing the other.
NF-κB
The transcription factor controlling most inflammatory cytokine production. The intervention point for KPV.
Off-label
Use of an approved drug outside its approved indication. Legal for a physician to prescribe; distinct from use of an unapproved compound, which has no label at all.
PCAC
The FDA's Pharmacy Compounding Advisory Committee, which advises on whether substances should be permitted for pharmacy compounding under section 503A. Its votes are advisory and non-binding, and they are not drug approvals.
Placebo-controlled / double-blind
A trial in which participants receive either the treatment or an inactive comparator, with neither participant nor investigator knowing which. It is the design that separates a real effect from expectation, and most peptide literature does not have it.
Pre-clinical
Research conducted in cell culture or animals, before human trials. Most peptide literature is pre-clinical, and this is the most important qualifier on this site.
Pulsatility
The natural rhythmic pattern of hormone secretion. GH signalling is pulse-sensitive, which is why continuous elevation is pharmacologically different from an amplified pulse.
Reconstitution
Dissolving lyophilised powder in a diluent. The diluent volume is a free choice that sets the concentration and therefore every subsequent measurement.
Research use only (RUO)
A labelling designation meaning the material is intended for laboratory use and is not approved, tested or manufactured for human administration.
Retrograde signalling
Communication from an organelle to the nucleus. MOTS-c is a mitochondrial-encoded peptide that does exactly this.
Somatostatin
The inhibitory hormone that brakes GH release. Ghrelin-receptor agonists suppress it; GHRH analogues do not.
Tachyphylaxis
Rapidly diminishing response to a repeated dose, usually from receptor desensitisation or downregulation. Frequently asserted to be absent for the repair peptides — but no study has tested for it, which is not the same thing.
Telomerase
The enzyme that extends telomeres. Reactivated in most human cancers, which is why inducing it in somatic cells is not an unambiguously good thing.
Titration
Stepwise dose escalation. In trials, steps and intervals are pre-specified with defined stopping rules; in community protocols they are usually gated on subjective response.
U-100
The insulin syringe standard: 100 units per millilitre. Every unit reading on this site assumes it.
VEGF / VEGFR2
Vascular endothelial growth factor and its receptor — the principal angiogenesis signalling axis, upregulated by BPC-157.
WADA
World Anti-Doping Agency. Publishes the Prohibited List annually; several compounds documented here are named on it explicitly.