Cholecystokinin-8 vs PACAP-38

Head-to-head comparison of Cholecystokinin-8 (Cholecystokinin (sulfated C-terminal octapeptide, CCK-8)) and PACAP-38 (Pituitary Adenylate Cyclase-Activating Polypeptide-38 (human PACAP-38)) — benefits, dosing, side effects, research data, and where to buy.

Research Score

PropertyCholecystokinin-8PACAP-38
CategoryEndocrine PeptidesCognitive Enhancement
Full NameCholecystokinin (sulfated C-terminal octapeptide, CCK-8)Pituitary Adenylate Cyclase-Activating Polypeptide-38 (human PACAP-38)
Molecular Weight1143.2 Da4534 Da
Half-Life1-2 minminutes
Amino AcidsDY(SO3H)MGWMDF-NH238 aa
Typical Dosephysiologic low-picomolar-nanomolar range|research-dependent10-100 µg preclinical range
Routeendogenous secretion|research IV/SCIntranasal
Purity≥98%≥98%
Studies Count97650
Research StatusEndogenousPre-clinical

Cholecystokinin-8 Benefits

  • gallbladder contraction
  • pancreatic enzyme release
  • satiety signaling

PACAP-38 Benefits

  • synaptic plasticity
  • BDNF upregulation
  • neuroprotection
  • memory consolidation

Cholecystokinin-8 Dosing

physiologic secretion|research-dependent

PACAP-38 Dosing

0.1-1 nmol ICV in rodents|10-100 µg intranasal in preclinical studies|single-dose or short repeated protocols

Cholecystokinin-8 Side Effects

  • abdominal cramping
  • nausea
  • biliary contraction

PACAP-38 Side Effects

  • headache-like effects
  • flushing
  • hypotension

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.

PACAP-38

PACAP-38 is one of the most studied endogenous neuropeptides for protecting neurons from ischemic and excitotoxic damage. Preclinical literature also links it to hippocampal plasticity and learning-related signaling, including increased BDNF expression.

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Common Stacking Partners

Cholecystokinin-8 stacks with:

gallbladderpancreassatiety

PACAP-38 stacks with:

citicolinealpha-gpcomega-3
gut-hormonesatiety-peptideendocrine-peptideneurotrophicbdnfsynaptic-plasticityneuroprotection