[The effect of pharmacological pretreatment on the long-term globally ischemic heart; lysosome, cyclic nucleotide and myocardial injury].

UNLABELLED: The effect of pretreatment on the 3 hrs globally ischemic heart assessed from the myocardial enzymes, lysosomal enzymes and cyclic nucleotides in coronary sinus blood was studied in mongrel dogs. Combined administration of CoQ10, Aprotinin, Betamethasone and Nifedipine was done as pretreatment.
RESULTS: m-AST, NAG and beta-Glucuronidase were significantly lower in the pretreatment group. Significant positive correlations were obtained in order between beta-Glucuronidase and NAG (r = 0.6869), m-AST and beta-Glucuronidase (r = 0.6590), m-AST and NAG (r = 0.5381), m-AST and CK-MB (r = 0.49), respectively. Significant increase in cAMP/cGMP ratio was observed in the control group after reperfusion. Before aortic occlusion, significant negative correlations were obtained between cAMP and beta-Glucuronidase, NAG, m-AST, and after 5 min of reperfusion, significant negative correlations were obtained between cGMP and NAG, m-AST and significant positive correlations between cAMP/cGMP ratio and NAG, m-AST. These data suggested the effectiveness of pretreatment, the relation between lysosomal enzyme release and the ischemic myocardial injury, and the usefulness of m-AST to evaluate the degree of myocardial injury. Moreover, the increase of cAMP/cGMP ratio suggested the ischemic myocardial injury, and cGMP in the ischemic condition, and cAMP in the non-ischemic condition affected lysosomal enzyme release.