Inhibition of norepinephrine autoxidation by a rat brain cortical factor.
Autoxidation in a physiological salt solution of 100-200 microM norepinephrine was measured, detecting formation of noradrenochrome spectrophotometrically at 480 nm. Samples from the 100,000 g supernatant of a rat cortex (10% w/v homogenate), diluted 100-fold by the reaction mixture, suppressed aminochrome formation approximately 90% for 5 h. The active principle, even in such high degree of dilution, proved to be a considerably more potent antioxidant than the metal chelating agent EDTA at optimal concentration. The antioxidant effect was most marked in the moderately alkaline pH range. The activity is associated with a relatively heat and acid stable, non-dialyzable protein (mol wt greater than 50,000), found in the 100,000 g supernatant.
D000818:Animals; D000975:Antioxidants / Q000494:pharmacology*; D001921:Brain / Q000378:metabolism*; D055598:Chemical Phenomena; D002621:Chemistry; D004492:Edetic Acid / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D008297:Male; D009638:Norepinephrine / Q000378:metabolism*; D010084:Oxidation-Reduction / Q000187:drug effects; D051381:Rats / Q000502:physiology*; D011919:Rats, Inbred Strains; D014020:Tissue Extracts / Q000494:pharmacology*
D000975:Antioxidants; D014020:Tissue Extracts; D004492:Edetic Acid; D009638:Norepinephrine