[Involvement of extracellular superoxide dismutase in cerebral blood flow regulation].
Physiological role of extracellular superoxide dismutase (SOD3) remains obscure. We tested the hypothesis that SOD3 regulates the equilibrium between superoxide (O2-) and nitric oxide (NO), thereby controlling vascular tone and cerebrovascular reactivity. In anesthetized rats local blood flow was measured in the striatum after intracerebral delivery of SOD-mimetic, SOD-inhibitor, NO-donor and NOS-inhibitor by microdialysis. We have found that SOD3 minimizes O2- levels preserving NO availability at resting conditions. SOD3 promotes NO mediated vasodilatation by scavenging O2- and basal SOD3 levels is able to inactivate O2- produced by 100% oxygen breathing preserving vasodilator effect of NO.
Demchenko
I T
IT
Gutsaeva
D R
DR
Moskvin
A N
AN
Zhiliaev
S Iu
SIu
D000818:Animals; D001783:Blood Flow Velocity / Q000187:drug effects; D002560:Cerebrovascular Circulation / Q000187:drug effects*; D009569:Nitric Oxide / Q000378:metabolism*; D051381:Rats; D013482:Superoxide Dismutase / Q000378:metabolism / Q000494:pharmacology*; D013481:Superoxides / Q000378:metabolism*; D014664:Vasodilation / Q000187:drug effects
D013481:Superoxides; D009569:Nitric Oxide; C499089:Sod3 protein, rat; D013482:Superoxide Dismutase