CSF β-EP in Headache and Depression

Abstract
Cerebrospinal fluid (CSF) levels of b-endorphin (b-EP) were measured in 9 migraineurs with interparoxysmal headache (MIH), in 13 patients with major depression in an active phase (5 suffered from MIH), and in 16 age-matched controls. b-EP was measured by specific RIA after gel-chromatography. While b-EP levels of depressed patients (58.5 ± 21.0 fmol/ml, M ± SD) were similar to those of controls (65.8 ± 26.6), those of migraineurs (15.0 ± 11.1) were significantly reduced (p < 0.01). In depressed patients also suffering from MIH, b-EP concentrations (22.8 ± 7.2, p < 0.05) were half those reported in depressed patients without pain problems. The reduced CSF b-EP levels in patients whose headache and depression coexist support the notion that this neuropeptide is concerned with chronic pain, independently of the affective state.