PACAP

What Is PACAP?

PACAP (Pituitary Adenylate Cyclase-Activating Polypeptide) is a neuropeptide that exists in two forms: PACAP-38 (38 amino acids, predominant) and PACAP-27 (27 amino acids). Discovered in 1989, PACAP belongs to the VIP/secretin/glucagon superfamily and shares 68% sequence homology with VIP. It acts on three receptors: PAC1 (PACAP-preferring), VPAC1, and VPAC2.

PACAP is one of the most potent neuroprotective peptides known. It protects neurons from apoptosis, excitotoxicity, oxidative stress, and ischemia through activation of cAMP/PKA, PI3K/Akt, and MAPK pathways. It is widely distributed in the nervous system, with particularly high concentrations in the hypothalamus, brainstem, and sensory ganglia.

Notably, PACAP has been implicated in migraine pathophysiology — IV PACAP-38 administration triggers migraine-like attacks in susceptible individuals. This has made PACAP a major drug target for migraine prevention, with anti-PACAP antibodies in clinical development.

What The Research Says

Preclinical neuroprotection studies show PACAP protects against stroke damage, traumatic brain injury, Parkinson's and Alzheimer's models, and retinal degeneration. The breadth of neuroprotective effects exceeds most other studied neuropeptides. PACAP-deficient mice show accelerated aging and neurodegeneration.

The migraine connection has generated significant pharmaceutical interest: anti-PACAP receptor antibodies are in clinical trials for migraine prevention. Paradoxically, PACAP's neuroprotective properties make it therapeutically interesting while its migraine-triggering properties make it a drug target for blocking.

📚 Key Reference: PMID: 19046989 (PACAP neuroprotection review)

Common Uses

• Neuroprotection research (stroke, TBI, neurodegeneration)
• Neuroscience research
• Migraine pathophysiology understanding
• Anti-aging/longevity neuroprotection (research)

Important Safety Information

IV PACAP triggers migraine in susceptible individuals and causes vasodilation, flushing, and hypotension. As a potent vasoactive peptide, cardiovascular monitoring is essential. Research use only with very limited human therapeutic data. Consult your provider.

Questions To Ask Your Provider

1. What neuroprotective application is being targeted?
2. Do I have a history of migraine that could be exacerbated?
3. What monitoring will be in place?

Regulatory Status

NOT FDA-approved. Research use only. Anti-PACAP antibodies (blocking PACAP) are in clinical trials for migraine.