Xanthine oxidase mediates myocardial injury after hepatoenteric ischemia-reperfusion.
OBJECTIVE
To determine if myocardial injury results from hepatoenteric ischemia-reperfusion. We also proposed to determine if this remote heart injury is mediated by a xanthine oxidase-dependent mechanism.


METHODS
Randomized, controlled animal study.


METHODS
University-based animal research facility.


METHODS
Thirty-six New Zealand white male rabbits, weighing 1.8 to 3 kg.


METHODS
Anesthetized rabbits were randomly assigned to one of four groups (n = 9 per group): a) a sham-operated group; b) a sham-operated group pretreated with sodium tungstate (xanthine oxidase inactivator); c) an aorta occlusion group; and d) an aorta occlusion group pretreated with sodium tungstate. Descending thoracic aorta occlusion was maintained for 40 mins with a 4-Fr Fogarty embolectomy catheter, followed by 2 hrs of reperfusion.


RESULTS
Myocardial injury, manifested by increased circulating creatine kinase-MB fraction activity, was significantly associated with aortic occlusion and reperfusion (p < .05). Sodium tungstate pretreatment significantly (p < .05) reduced circulating and myocardial xanthine oxidase activity. Xanthine oxidase inactivation by sodium tungstate significantly decreased circulating creatine kinase-MB fraction activity after hepatoenteric ischemia-reperfusion (p < .05). Finally, circulating creatine kinase-MB fraction activity was significantly associated with circulating xanthine oxidase activity (r2 = .85; p < .001).


CONCLUSIONS
We conclude that remote myocardial injury is caused by hepatoenteric ischemia-reperfusion. The pathoetiology of this myocardial injury involves a xanthine oxidase-dependent mechanism.
Nielsen
V G
VG
Department of Anesthesiology, University of Alabama at Birmingham 35233-6810, USA.
Tan
S
S
Baird
M S
MS
Samuelson
P N
PN
McCammon
A T
AT
Parks
D A
DA
D000818:Animals; D003402:Creatine Kinase / Q000097:blood; D007422:Intestines / Q000098:blood supply*; D007511:Ischemia / Q000503:physiopathology; D007527:Isoenzymes; D008102:Liver Circulation / Q000502:physiology*; D008297:Male; D015428:Myocardial Reperfusion Injury / Q000209:etiology*; D011817:Rabbits; D011897:Random Allocation; D017973:Tungsten Compounds / Q000494:pharmacology; D014969:Xanthine Oxidase / Q000037:antagonists & inhibitors / Q000097:blood / Q000502:physiology*
D007527:Isoenzymes; D017973:Tungsten Compounds; C025399:sodium tungstate(VI); D014969:Xanthine Oxidase; D003402:Creatine Kinase