Effects of Lymphatic Transport of Enzyme on Plasma Creatine Kinase Time-Activity Curves after Myocardial Infarction in Dogs

Because creatine kinase (CK) appears in cardiac lymph after myocardial infarction, this study was undertaken to determine whether lymph inactivates CK in vitro and whether interruption of cardiac lymph flow influences estimation of infarct size based on plasma CK changes in conscious dogs. After the effects of incubation of canine myocardial CK in native, deproteinized, or sulfhydrylfortified lymph and dialysates had been characterized; effects of interruption of cardiac lymph flow on plasma CK time-activity curves after coronary occlusion were assessed in 13 conscious dogs, seven of which had exteriorized occlusive snares around cardiac lymphatics as well as the left anterior descending coronary artery. Native and deproteinized lymph as well as lymph dialysate markedly inactivated CK in vitro with associated nonenzymatically mediated proteolysis detectable on SDS gels. CK released into blood after coronary occlusion compared to myocardial CK depletion was 50% less in dogs with lymphatic occlusion (P