A visual reference covering 18 widely-studied research compounds — what each one targets, which combinations are synergistic, and which pairings produce receptor competition or pharmacodynamic conflict.

Research Use Only Educational Resource 18 Compounds Reviewed 7 Stack Profiles

Peptide Synergy & Conflict Map

By System Peptides Research Network Editorial Last updated May 2026 12 min read Peer-reviewed receptor science

Research & Educational Use Only

This resource is intended for in vitro laboratory research and educational reference only. It is not medical advice and these compounds are not approved by the FDA for human consumption, therapeutic use, or clinical application. Real-world receptor pharmacology depends on dose, timing, route, and biological context. Researchers should consult primary literature and qualified professionals before designing protocols.

01 / Orientation

Three terms to know

A peptide is

A short chain of amino acids

Amino acids are the building blocks the body uses to make proteins. A peptide is just a short string of them — a brief signaling molecule.

A receptor is

A binding site on a cell

Cells display "locks" on their surface. A peptide is the matched "key" that fits — binding triggers a downstream signal: repair, grow, calm, fire.

A Dalton (Da) is

A unit of molecular weight

One Dalton ≈ the mass of a single hydrogen atom. So "1,419 Da" simply describes the molecule's size — bigger number, bigger molecule.

02 / Molecular Profile

Compound size and delivery

Molecular weight determines how a peptide can be delivered. Smaller peptides may be administered intranasally or sublingually; larger ones require subcutaneous injection because the gastrointestinal tract degrades them like food protein.

< 1,000 Da

Tiny

Class I

Small enough that some can be delivered as nasal sprays or sublingual drops. Cleared from the body quickly, so dosing is typically frequent.

EpitalonKPVPinealonGHK-CuSS-31IpamorelinSelankSemax

1,000–2,000 Da

Small

Class II

Still relatively small, but typically require injection for bioavailability.

Kisspeptin-10BPC-157

2,000–5,000 Da

Medium

Class III

Medium-sized and structurally complex. Injection only.

MOTS-cCJC-1295Thymosin α-1

> 5,000 Da

Protein-Sized

Class IV

Sensitive to heat and stomach acid. Strictly injectable, with cold-chain storage required to preserve tertiary structure.

TesamorelinTB-500 (full)

03 / Synergistic Stacks

Seven research stack profiles

A "stack" is a combination of compounds that target complementary mechanisms toward a unified research endpoint. Each profile below identifies the components, mechanism rationale, and timing considerations drawn from receptor pharmacology.

Stack 01 / Growth Hormone Axis

Growth Hormone Release

Two distinct receptors on the pituitary gland — GHRH and ghrelin (GHS-R1a) — engaged simultaneously for additive signaling rather than competition.

Amber

CJC-1295 (no DAC)

GHRH receptor agonist — sets the amplitude of the GH pulse.

Ipamorelin

Selective ghrelin receptor agonist — shapes pulse timing without raising cortisol or prolactin.

Timing

Pre-sleep, within 30 min of bedtime, to layer on the body's largest natural GH pulse during the first deep-sleep cycle.

Fasted State

Critical. Insulin and free fatty acids both blunt GH release. Allow 2–3 hr post-meal, with no fat or carbs in the window.

Mechanism: Each peptide binds a different pituitary receptor, so signals add rather than compete. CJC sets amplitude; Ipamorelin shapes timing.

Stack 02 / Tissue Regeneration

Tissue Repair

Three non-overlapping mechanisms targeting the recovery cascade: vascular supply, cell migration, and matrix synthesis.

Forest

BPC-157

Upregulates VEGFR2 to drive angiogenesis at the injury site — the supply infrastructure.

TB-500

Promotes actin-mediated cell migration to bring repair cells into position.

GHK-Cu (topical)

Modulates ~4,000 genes related to ECM remodeling and skin regeneration.

Timing

Flexible. BPC-157 often split AM + PM for steady tissue exposure. GHK-Cu applied to clean skin twice daily.

Fasted State

Not required. BPC-157 is unusually stable across fed/fasted states.

Pro tip: If running the GH stack at night, schedule the repair stack in the morning so each system has a clean signaling window.

Stack 03 / Mitochondrial Function

Mitochondrial Optimization

A multi-level approach: AMPK signaling, membrane integrity, cofactor pool, biogenesis, and salvage pathway protection.

Brick

MOTS-c

Activates AMPK — the cellular low-energy alarm that drives fuel utilization and autophagy.

SS-31

Binds cardiolipin in the inner mitochondrial membrane to prevent proton leak.

NAD+

Replenishes the cofactor pool that drives sirtuin activity and electron transport.

SLU-PP-332

ERR receptor agonist — drives mitochondrial biogenesis at the transcriptional level.

5-Amino-1MQ

Inhibits NNMT to preserve cellular NAD+ levels.

Timing

Morning. Aligns with circadian energy production rhythms. Late dosing — particularly NAD+ — can disrupt sleep.

Fasted State

Strongly preferred. AMPK only flips on when cellular energy is low; fasted morning dosing amplifies the effect.

Pro tip: MOTS-c + fasted cardio is among the most-studied "exercise mimetic" pairings. Break the fast 30–60 min after dosing.

Stack 04 / Cognitive & Neuroprotective

Neurocognitive Stack

Four non-competing mechanisms: stimulation, anxiolysis, antioxidant neuroprotection, and circadian alignment.

Indigo

Semax

Raises BDNF and NGF; modulates dopamine and serotonin tone.

Selank

Gentle GABA-A modulation for anxiolysis without sedation.

Pinealon

Crosses the blood-brain barrier; protects neurons from oxidative damage.

Epitalon

Supports pineal gland function and melatonin rhythm.

Timing

Semax AM (stimulating); Selank as needed; Pinealon PM; Epitalon at bedtime.

Fasted State

Not required. Most members are intranasal or subcutaneous — food doesn't materially affect absorption.

Pro tip: Avoid Semax after ~3 PM if sensitive to stimulation — it can disrupt sleep onset like late-day caffeine.

Stack 05 / Bioregulator Longevity

Longevity Bioregulators

Two short peptides from the Khavinson/St. Petersburg bioregulator framework — pineal and thymic gland support.

Teal

Epitalon

Tetrapeptide (Ala-Glu-Asp-Gly) studied for telomerase activation and pineal restoration.

Thymosin α-1

Activates TLR2/TLR9; matures T-cells and natural killer cells.

Timing

Thymosin α-1 AM (aligns with daily cortisol-driven immune cycle); Epitalon at bedtime (pineal/melatonin axis).

Fasted State

Not required. Thymosin α-1 is often run in cycles — daily for 1–2 weeks, then a break.

Note: Khavinson's bioregulator hypothesis proposes direct peptide-DNA interaction rather than classical receptor signaling. Mechanism remains an area of active research.

Stack 06 / Body Composition

Lean Body Composition

Same dual-receptor logic as Stack 01, but with FDA-approved Tesamorelin as the GHRH-side agonist.

Terracotta

Tesamorelin

Stabilized GHRH analog — FDA-approved for visceral adipose tissue reduction.

Ipamorelin

Ghrelin receptor agonist — amplifies the GH pulse without receptor overlap.

Timing

Bedtime. Tesamorelin labeling specifies once-daily bedtime dosing.

Fasted State

Critical. Same rules as Stack 01: 2–3 hr post-meal, no food 20–30 min after.

Pro tip: A second fasted-morning dose of Ipamorelin alone can drive an additional pulse. Do not double-dose Tesamorelin — receptor desensitization results.

Stack 07 / Reproductive Axis

Sex-Hormone Reset

Endogenous reactivation of the HPG axis via KISS1R signaling — orthogonal to all other stacks on this list.

Rose

Kisspeptin-10

KISS1R agonist — triggers GnRH → LH/FSH cascade for endogenous testosterone or estrogen production.

Timing

Morning aligns with natural testosterone/LH peak. Pulsatile protocols (small doses every few hours) better mimic physiological release.

Fasted State

Not required. Food does not significantly interfere with GnRH cascade.

Stacking note: KISS1R signaling is independent of every other system here, so Kisspeptin layers cleanly on top of any other stack.

04 / Pharmacodynamic Conflicts

Where combinations clash

Some pairings produce receptor competition, opposing signaling, or temporal conflicts. The following are documented points of caution drawn from receptor pharmacology.

Same Receptor

Tesamorelin + CJC-1295

Both are GHRH receptor agonists competing for the identical binding site. The result is not synergy — it's competitive antagonism risking receptor desensitization. Choose one, then layer Ipamorelin (different receptor) on top.

Opposing Effect

Thymosin α-1 vs. KPV

Thymosin α-1 upregulates immune signaling. KPV downregulates NF-κB-mediated inflammation. Different mechanisms, opposite directions — KPV may quiet the immune response Thymosin α-1 is meant to stimulate.

Wrong Timing

KPV in first 72 hr post-injury

Acute inflammation drives the recruitment of repair cells and angiogenic signaling. Suppressing it too early via KPV can blunt the very cascade that BPC-157 and TB-500 promote. Reserve KPV for chronic, not acute, inflammation.

Receptor Saturation

Multiple ghrelin-receptor releasers

Ipamorelin is the sole GHS-R1a agonist on this list. Adding a second (MK-677, GHRP-2, GHRP-6) does not amplify GH release — it desensitizes the receptor. Use one at a time.

Minor Note

Selank + Semax (high doses)

Both are degraded by prolyl endopeptidase. Most stacking protocols are uneventful, but very high concurrent doses may slow each other's clearance. Pharmacokinetic note rather than a true conflict.

Minor Note

SLU-PP-332 + GH stack

Overlapping downstream pathways for fat oxidation and energy production. Not a conflict, but expect diminishing returns rather than additive effect.

05 / Application Index

Goal-to-stack reference

Research Goal

Stack Profile

Avoid

GH axis modulation

CJC-1295 + Ipamorelin or Tesamorelin + Ipamorelin

CJC + Tesamorelin (same receptor)

Tissue repair

BPC-157 + TB-500 (+ topical GHK-Cu)

KPV in first 72 hr

Mitochondrial function

MOTS-c + SS-31 + NAD+ + SLU-PP-332 + 5-Amino-1MQ

—

Cognition + anxiolysis

Semax + Selank + Pinealon

—

Anti-aging / circadian

Epitalon + Thymosin α-1

—

HPG axis reset

Kisspeptin (mono or layered)

—

Immune support

Thymosin α-1

Concurrent KPV

Chronic inflammation

KPV

Active healing protocols

06 / Reference

Terminology glossary

AMPK: 5′ AMP-activated protein kinase — the cellular "low-energy alarm" that drives fuel utilization and autophagy when ATP is depleted.
BBB: Blood-brain barrier — selective interface protecting the CNS from circulating molecules. Smaller peptides (e.g., Pinealon) can cross.
BDNF: Brain-derived neurotrophic factor. Supports neuronal plasticity and survival.
ECM: Extracellular matrix — the structural network between cells. Modulated by GHK-Cu.
GABA-A: Major inhibitory ionotropic receptor in the CNS. Selank acts as a gentle modulator.
GH: Growth hormone — released by the anterior pituitary, primarily during slow-wave sleep.
GHRH: Growth hormone-releasing hormone — hypothalamic signal that triggers pituitary GH release. Mimicked by CJC-1295 and Tesamorelin.
GHS-R1a: Ghrelin receptor on the pituitary — second pathway for GH release. Activated by Ipamorelin.
KISS1R: Kisspeptin receptor. Triggers the GnRH → LH/FSH cascade upstream of testosterone/estrogen production.
NAD+: Nicotinamide adenine dinucleotide — essential cofactor for sirtuins and electron transport. Declines with age.
NF-κB: Master transcription factor regulating inflammatory gene expression. KPV suppresses its activation.
NNMT: Nicotinamide N-methyltransferase — enzyme that consumes NAD+ precursors. Inhibited by 5-Amino-1MQ.
Telomerase: Ribonucleoprotein enzyme that maintains telomeres (chromosome end caps). Studied as activated by Epitalon in human somatic cells.
VEGFR2: Vascular endothelial growth factor receptor 2 — drives angiogenesis. Upregulated by BPC-157.