Decreased storage stability of creatine kinase in a cardiac reperfusion solution.
Creatine kinase (CK; EC 2.7.3.2) has been used as an indicator of myocardial cellular damage. In this study we used a Krebs-Henseleit (KH) solution to reperfuse isolated rat hearts after 24 h of cold preservation and collected the KH reperfusate for assay of CK to assess cellular damage. We wanted to determine the stability of CK in the KH solution at different cold-storage temperatures and albumin concentrations. CK activity (mean +/- SEM) after one week of refrigeration (5 degrees C) was 93% +/- 1% of control values, whereas CK activity in nitrogen-frozen (-200 degrees C) samples was only 1.6% +/- 1% of control values, and that in samples frozen at moderately low temperatures (-10 degrees C) was 63% +/- 1% of control values. To enhance stability, we added albumin at several concentrations (49, 25, 12, and 6 g/L) to reperfusion collections in which CK had been previously determined. Specimens were frozen (-10 degrees C), then re-analyzed for CK weekly for three weeks. CK activity was maintained (100% +/- 5%) only in samples containing 25 g/L or more albumin. These data suggest that refrigeration (5 degrees C) for one week maintains normal CK activity in KH solution; however, if prolonged storage is necessary, a stabilizer such as albumin (greater than or equal to 25 g/L) will maintain analyte stability in frozen storage (-10 degrees C) for at least three weeks.
Dunphy
G
G
Department of Biology, University of Akron, OH 44325.
Ely
D
D
D000818:Animals; D003402:Creatine Kinase / Q000032:analysis*; D015925:Cryopreservation; D004795:Enzyme Stability; D007527:Isoenzymes; D009206:Myocardium / Q000201:enzymology*; D009926:Organ Preservation; D051381:Rats; D011919:Rats, Inbred Strains; D012996:Solutions; D013048:Specimen Handling / Q000379:methods
D007527:Isoenzymes; D012996:Solutions; D003402:Creatine Kinase