title: Absence of xanthine oxidase or xanthine dehydrogenase in the rabbit myocardium.
abstract: We directly measured the activity of the enzymes xanthine oxidase and xanthine dehydrogenase in rabbit and rat hearts, using a sensitive radiochemical assay. Neither xanthine oxidase activity nor xanthine dehydrogenase activity was detected in the rabbit heart. In the rat heart, xanthine oxidase activity was 9.1 +/- 0.5 mIU per gram wet weight and xanthine dehydrogenase activity was 53.0 +/- 1.9 mIU per gram wet weight. These results argue against the involvement of the xanthine oxidase/xanthine dehydrogenase system as a mechanism of tissue injury in the rabbit heart, and suggest that the ability of allopurinol to protect the rabbit heart against hypoxic or ischemic damage must be due to a mechanism other than inhibition of these enzymes.
authors.forename: C M
authors.initials: CM
authors.lastname: Grum
authors.forename: R A
authors.initials: RA
authors.lastname: Ragsdale
authors.forename: L H
authors.initials: LH
authors.lastname: Ketai
authors.forename: M
authors.initials: M
authors.lastname: Shlafer
mesh_terms: D000818:Animals; D007658:Ketone Oxidoreductases / Q000378:metabolism*; D009206:Myocardium / Q000201:enzymology*; D011817:Rabbits / Q000378:metabolism*; D051381:Rats; D013045:Species Specificity; D014968:Xanthine Dehydrogenase / Q000378:metabolism*; D014969:Xanthine Oxidase / Q000378:metabolism*
chemical_list: D014968:Xanthine Dehydrogenase; D014969:Xanthine Oxidase; D007658:Ketone Oxidoreductases