We describe a spectrophotometric kinetic assay for detecting creatine kinase MB isoenzyme activity in the 1 to 10 U/liter range. The MB isoenzyme was isolated [Clin. Chem. 20, 36 (1974)] and assayed (Rosalki method) with an Abbott ABA-100. Good reproducibility was demonstrated for MB isoenzyme activities near 1 U/liter (CV = 2.6%). Sera with normal or slightly increased total creatine kinase ac...

Gene variants, such as creatine kinase (CK) polymorphisms, have been suggested to explain the inter-individual CK response. However, this association is still unclear. Therefore, the purpose of this study was to analyze the association between the magnitudes of the CK response to exercise with the occurrence of muscle-CK-MM NcoI polymorphism in young healthy subjects. Blood CK activity was asse...

Spectrophotometry of CK-B subunit activity based on immunoinhibition is rapid and convenient. However, the low sensitivity limits clinical applications to serum samples with CK-B activities considerably above normal. A sensitive, but not optimized, bioluminescent assay of CK-B, also based on immunoinhibition, has been described. We improved this method by the use of an ADP concentration saturat...

The regulation of the specific activities of adenylate kinase (EC 2.7.4.3) and creatine kinase (EC 2.7.3.2) in myogenic cell lines is independent of cell fusion. The observed increases in enzyme specific activities are cell density dependent, and may be further broken down into contributions from an increase in enzyme activity per cell and a decrease in protein per cell. Only the former appears...

Adriamycin (ADM) is an anthracycline anti-neoplastic agent, whose clinical effectiveness is limited by severe side effects, including cardiotoxicity. The toxic effects of ADM are likely to be the consequence of the generation of free radicals. This study demonstrates that ADM induces significant changes in the activity of the oxidative sensitive enzyme creatine kinase (CK) in the heart in vivo ...

An automated (AutoAnalyzer) method for the colorimetric determination of creatine kinase activity in serum is described. This method includes reactivation of creatine kinase with cysteine, incubation of the active enzyme with creatine phosphate and adenosine diphosphate at 3750, and subsequent inactivation of enzyme and binding of csteine by phenylmercuric borate. The enzymatically produced cre...

Serum creatine kinase (CK) activities were investigated in elite male strength athletes (n = 20) during normal weight training and bodybuilding training (one training session per day), during high volume strength training (two sessions per day) and during strength training (one session per day) with the use of high dose synthetic androgens (five athletes in each subgroup). The findings demonstr...

Praecordial ST segment elevation was measured at 35 electrode positions in each of 40 patients admitted to a coronary care unit after acute transmural anterior myocardial infarction. Serial praecordial electrocardiographic maps were recorded to determine (a) the time course as well as reproducibility of measurements of ST segment alterations, and (b) the degree of correlation between the magnit...

We describe two cases, hospitalized patients, in whom the activity of creatine kinase (EC 2.7.3.2) isoenzyme-MB was above normal. Both are particularly noteworthy in that creatine kinase-BB and a macro creatine kinase form thought to be type II of mitochondrial origin were also present. The macro creatine kinase component in both cases co-migrated electrophoretically with creatine kinase-MM but...

Data from both in vivo and in vitro experiments demonstrated that glabridin and glabrene are similar to estradiol-17beta in their stimulation of the specific activity of creatine kinase, although at higher concentrations, but differ in their extent of action and interaction with other drugs. In pre-menopausal human bone cells, the response to estradiol-17beta and glabridin (at higher concentrat...