Buttery J E, Stuart S, Pannall P R
Department of Clinical Chemistry, Queen Elizabeth Hospital, Woodville, S.A., Australia.
Clin Biochem. 1992 Feb;25(1):11-3. doi: 10.1016/0009-9120(92)80039-j.
Unlike earlier studies on the stability of the CK-MB isoenzyme carried out on control sera and on semi-purified and purified CK isoenzymes, we have studied the stability of CK-MB measured electrophoretically in patient sera under different laboratory storage conditions. The values obtained if the test was done immediately were significantly higher than those done on stored samples. There was no difference between specimens stored at -20 degrees C overnight or kept at room temperature (RT) for a few hours, but values were significantly lower (p less than 0.005) in specimens left at RT for 6 h and then stored overnight at 4 degrees C. To determine the effects of longer storage, further specimens stored either at -20 degrees C or at 4 degrees C for up to 4 days were also tested for CK-MB stability by electrophoresis and by immunoinhibition and immunoenzymetric methods. The immunological methods were included in the study to assess method dependency of CK-MB stability. CK-MB was stable at -20 degrees C by all methods, but at 4 degrees C, CK-MB was stable only by immunological and not by electrophoretic (p less than 0.005) measurement. Specimens stored under adverse conditions (4-6 days at RT) showed 50% deterioration of CK-MB when measured electrophoretically but only about 20% when measured immunologically.
与早期在对照血清以及半纯化和纯化的肌酸激酶同工酶上进行的关于肌酸激酶MB同工酶稳定性的研究不同，我们研究了在不同实验室储存条件下，通过电泳法测定的患者血清中肌酸激酶MB的稳定性。如果立即进行检测，所获得的值显著高于对储存样本检测所得的值。在-20℃过夜储存的标本与在室温（RT）下放置数小时的标本之间没有差异，但在室温下放置6小时然后在4℃过夜储存的标本中，值显著更低（p<0.005）。为了确定更长时间储存的影响，还通过电泳法以及免疫抑制法和免疫酶法对另外一些在-20℃或4℃储存长达4天的标本进行了肌酸激酶MB稳定性检测。该研究纳入免疫学法是为了评估肌酸激酶MB稳定性的方法依赖性。通过所有方法检测，肌酸激酶MB在-20℃时均稳定，但在4℃时，仅通过免疫学法检测肌酸激酶MB稳定，而通过电泳法检测不稳定（p<0.005）。在不利条件下（室温下4 - 6天）储存的标本，通过电泳法检测时肌酸激酶MB有50%降解，但通过免疫学法检测时仅约20%降解。
