PACAP has well-known neuroprotective potential including
traumatic brain injury (TBI). Its level is up-regulated following various insults of the CNS in animal models. A few studies have documented alterations of
PACAP levels in human serum. The time course of post-ictal
PACAP levels, for example, show correlation with
migraine severity. Very little is known about the course of
PACAP levels following CNS injury in humans and the presence of
PACAP has not yet been detected in cerebrospinal fluid (CSF) of subjects with severe TBI (sTBI). The aim of the present study was to determine whether
PACAP occurs in the CSF and plasma (Pl) of patients that suffered sTBI and to establish a time course of
PACAP levels in the CSF and Pl. Thirty eight subjects with sTBI were enrolled with a Glasgow Coma Scale ≤8 on admission. Samples were taken daily, until the time of death or for maximum 10 days. Our results demonstrated that
PACAP was detectable in the CSF, with higher concentrations in patients with TBI.
PACAP concentrations markedly increased in both Pl and CSF in the majority of patients 24-48h after the injury stayed high thereafter. In cases of surviving patients, Pl and CSF levels displayed parallel patterns, which may imply the damage of the blood-brain barrier. However, in patients, who died within the first week, Pl levels were markedly higher than CSF levels, possibly indicating the prognostic value of high Pl
PACAP levels.