Lookup NU author(s): Dr Philip Manning,
Emeritus Professor Calum McNeil
Full text for this publication is not currently held within this repository. Alternative links are provided below where available.
Infusion of glyceryl trinitrate (GTN) into patients with migraine precipitates the onset of a migraine attack several hours after completion of the infusion. Using an infusion of GTN into anaesthetised rats, this study investigates the relationship of regional cerebral blood flux rCBF(ldf), cortical nitric oxide (NO) and cortical superoxide concentrations and the effect of sumatriptan on each variable. In saline treated animals, a 30 min infusion of GTN (2 μg kg-1 min-1, i.v.) was found to markedly increase cortical rCBF(ldf) (133±3% of baseline) and NO concentrations (141±13% of baseline). Superoxide levels exhibited an inverse relationship to NO levels, decreasing below basal to 48±14% of baseline. It is hypothesised that high NO levels during GTN infusion may decrease the detectable superoxide due to 'leeching' of the superoxide into low level peroxynitrite formation. In the presence of sumatriptan, a decrease below baseline in cortical rCBF(ldf) (82±5% of baseline) and NO concentration (64±13% of baseline) was observed throughout GTN infusion, although superoxide levels significantly increased above baseline by 105±14 nM (p<0.05, ANOVA post hoc LSD test). The mechanism for this action of sumatriptan is unknown but may include; modulation of cell redox state, NO scavenging or direct manipulation of superoxide release.
Author(s): Read SJ, Manning P, McNeil CJ, Hunter AJ, Parsons AA
Publication type: Article
Publication status: Published
Journal: Brain Research
Print publication date: 13/11/1999
ISSN (print): 0006-8993
ISSN (electronic): 1872-6240
PubMed id: 10564729
Altmetrics provided by Altmetric