Cholecystokinin-8 vs Leu-enkephalin
Head-to-head comparison of Cholecystokinin-8 (Cholecystokinin (sulfated C-terminal octapeptide, CCK-8)) and Leu-enkephalin (Tyr-Gly-Gly-Phe-Leu) — benefits, dosing, side effects, research data, and where to buy.
Research Score
| Property | Cholecystokinin-8 | Leu-enkephalin |
|---|---|---|
| Category | Endocrine Peptides | Pain Management |
| Full Name | Cholecystokinin (sulfated C-terminal octapeptide, CCK-8) | Tyr-Gly-Gly-Phe-Leu |
| Molecular Weight | 1143.2 Da | 555.63 Da |
| Half-Life | 1-2 min | 1-5 minutes in plasma |
| Amino Acids | DY(SO3H)MGWMDF-NH2 | 5 |
| Typical Dose | physiologic low-picomolar-nanomolar range|research-dependent | 0.1-5 ug per animal |
| Route | endogenous secretion|research IV/SC | Intrathecal / intracerebroventricular |
| Purity | ≥98% | ≥98% |
| Studies Count | 97 | 1000 |
| Research Status | Endogenous | Pre-clinical |
Cholecystokinin-8 Benefits
- ✓gallbladder contraction
- ✓pancreatic enzyme release
- ✓satiety signaling
Leu-enkephalin Benefits
- ✓delta-opioid activity
- ✓endogenous analgesic model
- ✓receptor-selective pharmacology
- ✓nociception pathway research
Cholecystokinin-8 Dosing
physiologic secretion|research-dependent
Leu-enkephalin Dosing
Intrathecal 0.1-5 ug per animal|Intracerebroventricular 0.1-2 ug per animal|In vitro 1-100 nM
Cholecystokinin-8 Side Effects
- ⚠abdominal cramping
- ⚠nausea
- ⚠biliary contraction
Leu-enkephalin Side Effects
- ⚠sedation
- ⚠constipation-like opioid effects
- ⚠very short plasma stability
Research Overview
Cholecystokinin-8
CCK-8 is a canonical gut hormone fragment with extensive documentation in digestive physiology and appetite control. Sulfation of the tyrosine residue is important for high-affinity receptor activity.
Leu-enkephalin
Leu-enkephalin is a standard tool in opioid receptor and pain-transmission research because it helps distinguish delta- from mu-preferring signaling. Its research value is high, but its clinical utility is limited by rapid enzymatic breakdown and delivery challenges.
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