Article

Concentration changes of malondialdehyde across the cerebral vascular bed and shedding of L-selectin during carotid endarterectomy.

Departments of Anesthesiology and Vascular Surgery (H-H.E.), University of Heidelberg, Heidelberg, Germany.
Stroke (impact factor: 5.73). 03/1999; 30(2):306-11. pp.306-11
Source: PubMed

ABSTRACT Oxidative stress has been postulated to account for delayed neuronal death due to ischemia/reperfusion. We investigated cerebral formation of malondialdehyde as an index of lipid peroxidation in relation to different sources of reactive oxygen species in patients undergoing carotid endarterectomy.
In 25 patients undergoing carotid endarterectomy, jugular venous-arterial concentration differences of brain metabolites, malondialdehyde, plasma total antioxidant status, and soluble P-selectin and L-selectin were measured. A carotid artery shunt (n=5) was placed only after complete loss of somatosensory evoked potentials, indicating a focal cerebral blood flow <15 mL/min per 100 g.
As an indication of cerebral lipid peroxidation, jugular venous-arterial malondialdehyde concentration differences were significantly enhanced before reperfusion, and an additional rise was observed 15 minutes after reperfusion. Plasma total antioxidant status significantly decreased during carotid artery occlusion only in patients with carotid artery shunt. This decrease was matched by cerebral formation of adenosine, hypoxanthine, and nitrite/nitrate. While jugular venous-arterial concentration differences of soluble P-selectin showed changes similar to those of malondialdehyde, the concentration difference for soluble L-selectin was enhanced exclusively at 15 minutes after reperfusion.
Short-term incomplete cerebral ischemia/reperfusion significantly enhanced cerebral lipid peroxidation, as indicated by malondialdehyde formation. The generation of reactive oxygen species by xanthine oxidase or nitric oxide metabolism might be involved in the induction of lipid peroxidation. The additional rise in cerebral release of malondialdehyde was found to coincide with a significant activation of polymorphonuclear leukocytes across the cerebral circulation.

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Keywords

15 minutes
 
25 patients undergoing carotid endarterectomy
 
brain metabolites
 
carotid artery
 
carotid artery occlusion
 
cerebral circulation
 
cerebral formation
 
cerebral lipid peroxidation
 
complete loss
 
focal cerebral blood flow <15 mL/min
 
jugular venous-arterial concentration differences
 
malondialdehyde formation
 
nitric oxide metabolism
 
patients undergoing carotid endarterectomy
 
plasma total antioxidant status
 
reactive oxygen species
 
Short-term incomplete cerebral ischemia/reperfusion
 
significant activation
 
somatosensory evoked potentials
 
xanthine oxidase
 

M A Weigand