Vasoactive intestinal peptide in cerebrospinal fluid.

Immunoreactive vasoactive intestinal peptide (VIP) was measured in lumbar and ventricular cerebrospinal fluid (CSF) from patients with various neurological disorders and in 2 hour aliquots of cisternal fluid removed continuously from rhesus monkeys. Although most of the VIP in concentrated pools of human ventricular fluid and of monkey cisternal fluid co-eluted with synthetic porcine VIP28 on a column of Sephadex G-25 superfine, there was evidence that smaller immunoreactive fragments were also present. A circadian pattern of CSF VIP concentration was observed in 2 of the 3 monkeys studied, with highest levels occurring at night and lowest during the day. Ventricular fluid VIP levels were highest in hydrocephalic children and lowest in patients with multiple sclerosis or epilepsy, while VIP was not detectable in ventricular fluid from patients in coma following a severe head injury. There were no significant differences in VIP concentrations in CSF from patients with dystonia. Parkinson's disease, or Alzheimer's disease, suggesting that VIP containing neurons are not affected in these disorders. Lumbar fluid VIP levels were low in patients undergoing aneurysm surgery. Since VIP is a potent vasodilator, these findings may have important implications in relation to the development of vasospasm following subarachnoid hemorrhage.