Studies on the change of electrophoretic mobility and the decay of catalytic activity of brain-type creatine kinase isoenzyme (CK-BB) following incubation at 37 °C

Abstract

Incubation of CK-BB in serum (1:3, v/v) at 37°C for 3 h caused a change of its electrophoretic mobility and decay of its catalytic activity. Similar effects were observed following incubation in water. Incubation in saline somehow preserved the electrophoretic mobility but not the catalytic activity. No effect was noted when incubated at 4°C for 3 h. Further study on the rate of decay revealed that the decay in albumin solution (1:50, v/v) is quite similar to that in serum. More dramatic decay was noted when incubated in water and less when incubated in saline. It was further shown that the higher the incubation temperature (4°C, 25°C or 37°C) the faster the decay. The rate of decay of CK-MM was much slower in all conditions of incubation. Determination of isoenzyme activities by means of an immunoprecipitation method again demonstrated that CK-BB lost a great deal of its catalytic activity following incubation at 37°C for 1 h, and hence falsification of the isoenzyme pattern.