A novel concept on the pathogenetic mechanism underlying ischaemic brain oedema: relevance of free radicals and eicosanoids.
A survey on literature reports and our own experimental studies on the pathogenetic mechanisms underlying ischaemic brain oedema is given and a new concept proposed. In regional incomplete ischaemia the lipoxygenase activity is enhanced, presumably caused by an increase of free radicals and hydroperoxides, leading to an enhancement of endothelial Na+, K+-AtPase and increased sodium and water transport from blood to brain. The aggravation of brain oedema and post-ischaemic hypoperfusion following recirculation appears to be mainly due to an activation of the cyclo-oxygenase pathway with release of oxidants from PGG2, which causes non-specific but detrimental damage to the endothelial and parenchymal cells. This new concept may open future perspectives in treatment which are briefly discussed.
Asano
T
T
Department of Neurosurgery, Saitama Medical Centre, Saitama Medical School, Tokyo, Japan.
Shigeno
T
T
Johshita
H
H
Usui
M
M
Hanamura
T
T
D000818:Animals; D001095:Arachidonic Acids / Q000494:pharmacology; D001696:Biomechanical Phenomena; D001812:Blood-Brain Barrier; D001929:Brain Edema / Q000209:etiology*; D002545:Brain Ischemia / Q000150:complications* / Q000201:enzymology / Q000503:physiopathology; D002196:Capillaries / Q000201:enzymology; D002560:Cerebrovascular Circulation; D004537:Eicosanoic Acids / Q000502:physiology*; D005609:Free Radicals; D006801:Humans; D015289:Leukotrienes; D008054:Lipid Peroxides / Q000494:pharmacology; D008084:Lipoxygenase / Q000096:biosynthesis / Q000378:metabolism; D010100:Oxygen / Q000502:physiology*; D011451:Prostaglandin-Endoperoxide Synthases / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism; D013997:Time Factors
D001095:Arachidonic Acids; D004537:Eicosanoic Acids; D005609:Free Radicals; D015289:Leukotrienes; D008054:Lipid Peroxides; C025086:15-hydroperoxy-5,8,11,13-eicosatetraenoic acid; D008084:Lipoxygenase; D011451:Prostaglandin-Endoperoxide Synthases; D000254:Sodium-Potassium-Exchanging ATPase; D010100:Oxygen