Lactate dehydrogenase and creatine kinase activities in isolated edema fluid and peripheral blood in cold-induced brain edema.

A study of the alterations in lactate dehydrogenase and creatine kinase isoenzyme patterns in isolated grey and white matter edema fluid and in peripheral blood is described with a view to possible clinical use in severe brain-injury. The breakdown of the blood-brain barrier, caused by the infliction of a cold injury to the cerebral cortex of cats, resulted in a shift in the LD isoenzyme distribution in favour of the faster moving fractions and the appearance of brain-type CK in the peripheral blood. Total lactate dehydrogenase activity demonstrated no statistical significant changes during the experiment and total creatine kinase showed only slight increased values in the samples collected simultaneously with the infliction of a cold lesion. This strongly suggests that measurements of these parameters in peripheral blood are of little value as indicators of brain damage. Alterations in isoenzyme patterns observed in edema fluids are reflected in peripheral blood. The presence, therefore, of brain-type creatine kinase accompanied by a relative high amount of lactate dehydrogenase H-sub unit in peripheral blood, can be considered as adequate indices of severe brain damage.