Radical trapping by PBN during reperfusion in rabbit gastric mucosa.
Oxygen free radicals have been considered as a cause of ischemia-reperfusion injury in several organs, but this injury in a stomach, containing acid, may progress to severe damage. Thus, we examined the effect of ischemia-reperfusion and milk-intake on rabbit gastric mucosa. The gastric mucosal blood flow was increased after milk-intake, and gastric rupture was detected. Superoxide dismutase activity measured by an improved nitroblue tetrazolium reduction method and thiobarbituric acid reactive substances in serum is increased during ischemia-reperfusion and milk-intake. By using alpha-phenyl N-tert-butyl nitrone (PBN) as a spin trap and electron paramagnetic resonance (EPR), we detected lipidic radicals from tissue samples in chloroform-methanol solvent only during reperfusion and milk-intake period; no signal was detected before. The EPR signal of spin adducts obtained in the sample after ischemia-reperfusion and milk-intake would be a mixture of peroxyl and alkoxyl radicals from the analysis of coupling constants.
Sonoda
M
M
First Department of Biochemistry, Saitama Medical School, Japan.
Asakuno
G
G
Matsuki
M
M
Satomi
A
A
Ishida
K
K
Sakagishi
Y
Y
D000818:Animals; D005609:Free Radicals; D005753:Gastric Mucosa / Q000098:blood supply / Q000378:metabolism*; D007511:Ischemia / Q000378:metabolism; D008892:Milk / Q000378:metabolism; D011817:Rabbits; D015427:Reperfusion Injury / Q000378:metabolism*; D013482:Superoxide Dismutase / Q000378:metabolism*
D005609:Free Radicals; D013482:Superoxide Dismutase