Stroke, Vol 22, 215-220, Copyright © 1991 by American Heart Association
P Gaetani, F Marzatico, D Lombardi, D Adinolfi and R Rodriguez y Baena
Free radicals and lipid peroxidation of membrane fatty acids are thought to
play a role in the pathogenesis of arterial vasospasm and the
physiopathologic patterns of neuronal damage after subarachnoid hemorrhage.
We have evaluated the effects of treatment with either high- dose
methylprednisolone every 8 hours or a single dose of U74006F on the
temporal profile of ex vivo synthesis of four selected eicosanoids in brain
slices after experimental induction of subarachnoid hemorrhage in rats.
Prostaglandins D2 and E2, prostacyclin and leukotriene C4 levels were
determined by radioimmunoassay after 1-hour incubation of the brain slices.
The synthesis of prostaglandin D2 and 6- ketoprostaglandin F1 alpha at 48
hours after subarachnoid hemorrhage was significantly higher when compared
to sham-operated animals (p = 0.01); prostaglandin E2 release was
significantly enhanced at 6 hours after subarachnoid hemorrhage (p = 0.01).
The release of the lipoxygenase metabolite was significantly enhanced at 1,
6, and 48 hours after subarachnoid hemorrhage induction. Both treatment
regimens significantly reduced the ex vivo synthesis of prostaglandin D2,
prostaglandin E2, and leukotriene C4 at 1, 6, and 48 hours after
subarachnoid hemorrhage, whereas the effects on 6-ketoprostaglandin F1
alpha synthesis differed in the two treatment groups. U74006F enhanced the
synthesis of prostacyclin metabolite in the early phase after subarachnoid
hemorrhage, and high-dose methylprednisolone reduced the increasing
synthesis at 48 hours. A strict comparison between the two treatments was
not possible because of the different modalities of administration.
However, these data suggest that the antioxidant effect of single-dose
treatment with U74006F influenced the early and delayed effects on
enzymatic lipid peroxidation, whereas the effects of methylprednisolone
administration every 8 hours were more significant in the delayed phase.
ARTICLES
Effect of high-dose methylprednisolone and U74006F on eicosanoid synthesis after subarachnoid hemorrhage in rats
Department of Surgery, University of Pavia, Italy.
|
Stroke Home | Subscriptions | Archives | Feedback | Authors | Help | AHA Journals Home | Search Copyright © 1991 American Heart Association, Inc. All rights reserved. Unauthorized use prohibited. |