ACTH(4-10)
Also known as: Met-Glu-His-Phe-Arg-Trp-Gly-Lys-Pro-Val · adrenocorticotropic hormone fragment 4-10
The parent 4-10 fragment of adrenocorticotropic hormone from which Semax derives — the classical ACTH-fragment cognitive-research peptide with foundational historical significance in the vasopressin/ACTH memory-peptide programme.
ACTH(4-10) is the parent 4-10 fragment of adrenocorticotropic hormone from which Semax derives — classical historical reference in the ACTH-fragment cognitive-peptide research programme.
Evidence tier: C — preclinical / mechanistic evidence only
- Category
- Cognitive Enhancement
- Half-life
- Short plasma half-life (minutes)
Section 1
Overview
ACTH(4-10) is the 4-through-10 residue fragment of adrenocorticotropic hormone — the pituitary peptide that stimulates cortisol release from the adrenal cortex. The fragment retains ACTH's cognitive-relevant central effects while lacking the endocrine (cortisol-releasing) activity of the parent hormone; the discovery that this separation was possible was the foundational insight that motivated the modern ACTH-fragment cognitive-peptide research programme.
The compound is the direct parent from which Semax derives. Where Semax adds a proline-glycine-proline C-terminal tail to stabilise the fragment against proteolysis, ACTH(4-10) is the unmodified parent fragment. Its plasma half-life is substantially shorter than Semax, limiting its practical research applications, but the compound retains historical and mechanistic significance.
Direct current research use of ACTH(4-10) is limited given the substantial pharmacokinetic advantages of Semax and other analogues. The peptide is included on this reference to complete the classical ACTH-fragment cognitive-peptide family coverage and to provide the mechanistic-and-historical context for Semax's development.
Section 2
Discovery & History
- Identified in the 1960s-70s as the cognitive-relevant fragment of ACTH through systematic peptide-fragment characterisation of the parent hormone.
- Characterised extensively across the 1970s-80s Dutch and Russian research programmes as the foundational reference compound for the ACTH-fragment cognitive-peptide research trajectory.
- Directly informed the development of Semax (Russia) and Org 2766 (Netherlands) as pharmacokinetically-improved analogues addressing the parent fragment's short plasma half-life.
- Never entered clinical development towards marketing authorisation; the derivative analogues (Semax, Org 2766) captured the practical research and clinical-evaluation applications.
- Retains research-chemical availability and historical significance in the ACTH-fragment cognitive-peptide research programme.
Section 3
Mechanism of Action
- 1ACTH-fragment-family central pharmacology without the endocrine cortisol-releasing activity of parent ACTH — the foundational pharmacological property that motivated the entire ACTH-fragment cognitive-peptide research programme.
- 2Reported BDNF and NGF induction in preclinical models — the neurotrophin-induction mechanism that Semax subsequently characterised more extensively and that provides the shared mechanistic framework across the ACTH-fragment analogue family.
- 3Central effects on memory-relevant neurocircuitry consistent with the broader ACTH-fragment family pharmacology, though the mechanism characterisation is less developed than for Semax owing to the pharmacokinetic limitations that restricted the compound's research use.
- 4Modulation of monoamine turnover (serotonin, dopamine) reported in some preclinical characterisation, providing additional angles for the cognitive effects and mechanistic overlap with the Semax mechanism-of-action framework.
- 5Reported effects on stress-response and attention research endpoints in early behavioural pharmacology work, establishing the compound's research-tool relevance for cognitive-relevance research contexts.
- 6The short plasma half-life limits the practical mechanism characterisation depth relative to Semax and other stabilised analogues.
Section 4
Researched Benefits
Findings reported in the published preclinical and clinical literature. Effects in research contexts do not constitute claims of therapeutic benefit in humans.
- 1Historical foundational significance as the parent fragment from which Semax, Org 2766, and the broader ACTH-fragment cognitive-peptide family derive.
- 2Retains ACTH's cognitive-relevant central effects without the endocrine consequences of the parent hormone — the foundational pharmacological property.
- 3Reference compound for the ACTH-fragment mechanism-of-action framework across the analogue family.
- 4Available as research chemical for specialised historical-context research applications.
- 5Provides mechanistic-and-historical context for interpreting the modern ACTH-fragment cognitive-peptide research (Semax, N-Acetyl Semax, Org 2766).
- 6Limited current research use owing to pharmacokinetic disadvantages relative to stabilised analogues.
Section 5
Theoretical Dosing & Protocols
| Route | Dosage | Frequency | Duration |
|---|---|---|---|
| Parenteral (research) | Microgram-range doses in classical research protocols | Multiple daily doses required owing to short plasma half-life | Short courses in classical research contexts |
Note: The short plasma half-life makes ACTH(4-10) less practical than Semax for most research applications; specific research-context use is generally limited to mechanistic-comparison studies.
Section 6
Administration Routes
- Parenteral administration (subcutaneous, intramuscular, intravenous) — the standard routes in the classical research literature.
- Intranasal administration used in some research contexts but less effective than for stabilised analogues.
- Oral administration is not viable — the peptide is degraded by gastrointestinal proteases.
Section 7
Safety Profile
Commonly reported
- · Generally well-tolerated in the classical research at studied doses.
- · Injection-site reactions with parenteral administration.
- · Occasional mild transient effects during administration.
- · No dependence or withdrawal phenomena documented.
Rare / theoretical
- · Long-term safety data is very limited given the compound's restricted historical research use.
- · Rare hypersensitivity reactions.
- · Residual endocrine effects from the ACTH-fragment origin — minimal at studied research doses.
- · Theoretical interactions with ACTH-family or vasopressin-family pharmaceuticals.
Contraindications
- · Not authorised for human use in the UK.
- · Pregnancy and lactation — no controlled data.
- · Known hypersensitivity to peptide components.
Section 8
UK & EU Regulatory Context
United Kingdom
Not a licensed medicine in the UK. Research chemical / historical significance only.
European Union
Not approved by the EMA.
Section 9
Clinical Studies Summary
ACTH(4-10) foundational cognitive-fragment characterisation
The classical 1960s-70s characterisation studies establishing ACTH(4-10) as the cognitive-relevant fragment of the parent ACTH hormone, with separation of the central memory effects from the peripheral endocrine cortisol-releasing activity. Provides the foundational reference for the entire ACTH-fragment cognitive-peptide research programme.
ACTH(4-10) memory-modulation research
Classical animal and human research characterising ACTH(4-10)'s memory-modulation effects across multiple learning and cognitive-endpoint paradigms, establishing the parent-fragment pharmacological framework that the derivative analogues (Semax, Org 2766) subsequently extended and refined.
ACTH(4-10) versus derivative analogues comparative pharmacology
Comparative pharmacology studies characterising ACTH(4-10)'s pharmacokinetic and pharmacodynamic profile relative to the stabilised derivative analogues (Semax, Org 2766), demonstrating the pharmacokinetic disadvantages of the parent fragment and the motivation for the analogue-development programmes that produced the practical research and clinical tools.
Section 10
Frequently Asked Questions
Section 10a
Practical Research Guidance
Cycle guidance
Reconstitution & storage
UK sourcing notes
Section 11
Sourcing for Laboratory Research
Sourcing ACTH(4-10) for laboratory research
Researchers in the United Kingdom and elsewhere typically obtain ACTH(4-10) from specialist research-chemical suppliers. Purity, third-party testing, and supplier transparency are the principal differentiators worth evaluating before placing an order. The two suppliers below are commonly referenced in UK research contexts.
Reminder: research peptides are sold strictly for in vitro and preclinical laboratory purposes. Importation or supply for human consumption is not permitted under UK medicines legislation.