PACAP38 induces migraine-like attacks in patients with migraine without aura

What Was Tested

Researchers studied PACAP in the context of migraine in this randomized controlled trial publication.

Pituitary adenylate cyclase activating peptide-38 (PACAP38) is a strong vasodilator found in trigeminal sensory and parasympathetic perivascular nerve fibers.

The researchers therefore hypothesized that infusion of PACAP38 would cause headache in healthy subjects and migraine-like attacks in migraine patients.

Who Took Part

The study group was 12 patients.

PubMed indexes the participants as young adults, adults and middle-aged adults, both men and women.

How the Study Was Run

In design terms this was a randomized, double-blind, placebo-controlled and crossover study.

Because people in this PACAP study were split into groups at random, differences between the groups are less likely to reflect who happened to join each one.

As a double-blind PACAP study, the assignments were hidden from both participants and investigators until the end.

The comparison arm used a placebo, so changes seen with PACAP could be set against what happens without it.

In the crossover set-up each of the patients took both PACAP and the comparison in turn, acting as their own control.

What Was Measured

Headache was scored on a verbal rating scale (VRS) during hospital (0-2 h) and post-hospital (2-12 h) phases.

Topics PubMed links to this paper include Blood Flow Velocity, Blood Pressure, Flushing, Headache, Heart Rate, Middle Cerebral Artery and Migraine without Aura.

What This Means in Plain Language

The paper is a randomized, double-blind and placebo-controlled study of PACAP in 12 patients in people with migraine.

With fewer than 40 people, it is a small study, so it is better read as an early signal for further research than as a settled answer.

The publication is from 2009 (Brain : a journal of neurology), a journal based in England.

More context: the PACAP compound page, Migraine research.