Purine and oxypurine production in mitochondria of ischemic and reperfused myocardium.
The present study was undertaken to determine whether significant breakdown of adenine nucleotides to purine bases and oxypurines occurred in mitochondria following myocardial ischemia and ischemia followed by reperfusion, and whether allopurinol prevented this effect. The adenine nucleotides adenosine, hypoxanthine, xanthine and uric acid were measured in the mitochondria and the results suggest that breakdown did occur. Malondialdehyde concentration was determined to gauge lipid peroxidation. This substance did not increase during ischemia or reperfusion, but did so in the presence of allopurinol. Xanthine dehydrogenase was converted to xanthine oxidase during reperfusion and the activity of both enzymes were inhibited by allopurinol. The results also suggested the presence of a mitochondrial 5'-nucleotidase. We conclude that significant breakdown of adenine nucleotide took place in myocardial mitochondria during ischemia and ischemia followed by reperfusion and that allopurinol may have a protective effect.
van Jaarsveld
H
H
Department of Chemical pathology, University of the Orange Free State, Bloemfontein, Republic of South Africa.
Barnard
H C
HC
Barnard
S P
SP
Maartens
J J
JJ
Potgieter
G M
GM
D000227:Adenine Nucleotides / Q000378:metabolism*; D000241:Adenosine / Q000378:metabolism; D000493:Allopurinol / Q000494:pharmacology; D000818:Animals; D019271:Hypoxanthine; D007042:Hypoxanthines / Q000378:metabolism; D008297:Male; D008315:Malondialdehyde / Q000378:metabolism; D008929:Mitochondria, Heart / Q000378:metabolism*; D015428:Myocardial Reperfusion Injury / Q000378:metabolism* / Q000517:prevention & control; D011687:Purines / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D014527:Uric Acid / Q000378:metabolism; D019820:Xanthine; D014968:Xanthine Dehydrogenase / Q000378:metabolism; D014970:Xanthines / Q000378:metabolism
D000227:Adenine Nucleotides; D007042:Hypoxanthines; D011687:Purines; D014970:Xanthines; D019820:Xanthine; D014527:Uric Acid; D019271:Hypoxanthine; D008315:Malondialdehyde; D000493:Allopurinol; D014968:Xanthine Dehydrogenase; D000241:Adenosine