Cholecystokinin (CCK)
Also known as: CCK, Pancreozymin, CCK-8, CCK-33
Overview
Cholecystokinin (CCK) is a peptide hormone found in multiple forms (CCK-8, CCK-33, CCK-58) secreted by enteroendocrine I-cells of the duodenum and jejunum in response to dietary fat and protein. It is among the most important physiological satiety signals, acting centrally via vagal afferents to terminate meals and promote satiety. CCK also stimulates gallbladder contraction and pancreatic enzyme secretion, facilitating fat and protein digestion. In the CNS, CCK acts as a neuromodulator influencing anxiety, analgesia, and memory formation.
Mechanism of Action
CCK binds two GPCRs: CCK-1R (expressed in vagal afferents, gallbladder, pancreas, enteric neurons) and CCK-2R (expressed in CNS, stomach). CCK-1R activation via Gq/11 stimulates inositol phospholipid turnover and intracellular calcium release. In the GI tract, this causes gallbladder contraction, pancreatic acinar cell exocytosis of digestive enzymes, and Oddi sphincter relaxation. Vagal CCK-1R activation transmits satiety signals to nucleus tractus solitarius and hypothalamic POMC neurons. The CNS CCK-2R mediates anxiety-like responses, analgesia modulation, and dopaminergic/opioidergic interactions.
Potential Benefits
- Physiological satiety signaling and meal termination
- Pancreatic enzyme secretion stimulation for fat/protein digestion
- Gallbladder contraction promoting bile flow
- CNS neuromodulation (anxiety, memory, analgesia)
- Research target for anti-obesity drug development (CCK-1R agonists)
Dosage Protocols
The following reflects doses used in published research studies. This is not medical advice. Consult a qualified healthcare professional.
| Beginner | Diagnostic use only (gallbladder function) |
| Intermediate | N/A |
| Advanced | N/A |
| Cycle Duration | N/A |
Sincalide (Kinevac, CCK-8) is FDA-approved diagnostic for gallbladder imaging. Research use for satiety/panic studies.
Use our Reconstitution Calculator to determine exact syringe units for your protocol.
Routes of Administration
Intravenous 100%
Diagnostic administration only.
Read our full Routes of Administration Guide for detailed comparison of all delivery methods.
Stacking Protocols
Popular research stacks involving Cholecystokinin (CCK):
Not Applicable
CCK is a diagnostic/research agent — not used in therapeutic stacking. CCK-A agonists were explored for obesity but failed.
Explore our complete Peptide Stacking Guide for more combinations and safety considerations.
Reconstitution
| Storage | Refrigerate 2-8°C. Use within 24 hours of reconstitution. |
|---|
Diagnostic kit — follow package insert.
Need exact syringe measurements?
Amino Acid Sequence
Asp-Tyr(SO3H)-Met-Gly-Trp-Met-Asp-Phe-NH2 (CCK-8 sulfated; biologically active form)
Side Effects & Safety
- Nausea at pharmacological doses
- Abdominal cramps
- CNS anxiety-like effects via CCK-2R
Safety & Contraindications
This information is for educational purposes only. Consult a qualified healthcare provider before using any peptide.
Pregnancy / Lactation
Bleeding Disorders
Active Skin Infection at Injection Site
Pharmacokinetics
| Half-Life | ~2.5 minutes (CCK-8) |
|---|---|
| Storage | Refrigerate 2-8°C. Protect from light. |
Synergistic Compounds
The following compounds have been studied alongside Cholecystokinin (CCK) for potential complementary or synergistic effects:
Learn More
References & Further Reading
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