The in vitro stability of creatine kinase isoforms was examined by separation with high voltage electrophoresis. The effect of inhibitors of carboxypeptidase was evaluated. Preservation of samples is essential to inhibit in vitro changes in isoform pattern. EDTA at a final concentration of 15 mmol/L is recommended. Using appropriately preserved samples, normal reference intervals for the MM isoforms have been established.
ChapelleJPHeusghenC.Further heterogeneity demonstrated for serum creatine kinase isoenzyme MM. Clin Chem1980; 26: 457–62.
2.
PuleoPRGuadagnoPARobertsREarly diagnosis of acute myocardial infarction based on assay for subforms of creatine kinase-MB. Circulation1990; 82: 759–64.
MorelliRLEmilsonBRapaportE.MM-CK subtypes diagnose reperfusion early after myocardial infarction. Am J Med Sci1987; 293: 139–49.
6.
JaffeASSerotaHGraceASobelBE. Diagnostic changes in plasma creatine kinase isoforms early after the onset of acute myocardial infarction. Circulation1986; 74: 105–9.
7.
MorelliRLCarbonCJEmilsonBAbendscheinDRRapaportE.Serum creatine kinase MM isoenzyme sub-bands after acute myocardial infarction in man. Circulation1983; 67: 1283–9.
8.
KeshgeglanAABhagatPKLeaseJABaiocchiJ.Creatine kinase MM isoforms in serum after cardiac surgery. Clin Chem1988; 34: 1067–70.
9.
NoharaRSobelBEJaffeASAbendscheinDR. Quantitative analysis for isoforms of creatine kinase MM in plasma by chromatofocusing with on-line monitoring of enzyme activity. Clin Chem1988; 34: 235–9.
10.
ChapelleJP. Serum creatine kinase MM sub-band determination by isoelectric focusing: A potential method for monitoring of myocardial infarction. Clin Chim Acta1984; 137: 273–81.
11.
WilliamsJMarshallT.Heterogeneity of serum creatine kinase isoenzyme MM in myocardial infarction: Standardization of patterns by use of cord blood serum. Clin Chem1988; 34: 398–401.
12.
PuleoPRGuadagnoPARobertsRPerrymanB.Sensitive rapid assay of subforms of creatine kinase MB in plasma. Clin Chem1989; 35: 1452–5.
13.
Mercaptoethanol. Hazard Datasheets, BDH1991: 640.
14.
YusufSPearsonMSterryHThe entry ECG in the early diagnosis and prognostic stratification of patients with suspected acute myocardial infarction. E Heart J1984; 5: 716–26.
15.
ZarlingEJSextonHMiloronP.Failure to diagnose acute myocardial infarction. JAMA1983; 250: 1117–81.
16.
BayerAJChandraJSForangRRPathyKSJ. Changing presentation of myocardial infarction with increasing age. J Am Geriatr Soc1986; 34: 263–6.