Possible mechanisms for the increase in alkaline phosphatase activity of lyophilized control material.

نویسندگان

  • A F Smith
  • B A Fogg
چکیده

The increased alkaline phosphatase (EC 3.1.3.1) activity of reconstituted lyophilized control sera has recently been the focus of considerable interest because of its possible implications for quality-control procedures. We confirm that these reconstituted materials show a temperature-dependent increase in alkaline phosphatase activity, but could show no alteration in activity of fresh sera. The rate of increase in activity was unaffected by dialysis of the reconstituted material, and occurred more rapidly in dilute solutions. Studies with acrylamide gel electrophoresis and Sephadex G-200 gel filtration showed that, immediately after reconstitution, a high-molecularweight alkaline phosphatase component predominated; during subsequent spontaneous activation this component decreased, and there was a concomitant increase in a low-molecular-weight alkaline phosphatase component. The results obtained when the reconstituted material was extracted with butanol suggest that the observed changes in alkaline phosphatase activity may be attributed to the breakdown of a complex between alkaline phosphatase and lipoprotein.

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

منابع مشابه

Alkaline phosphatase: lability in fresh and frozen human serum and in lyophilized control material.

On storage, the activity of alkaline phosphatase (AP) in human serum increases. This has been known, but largely ignored, for 40 years. Improved instrumentation makes this lability more obvious and more important because errors from other sources have been decreased. With a stabilized spectrophotometer we quantitated the effects of time and temperature on AP activity of human sera and of lyophi...

متن کامل

Protective effect of glycerol against the increase in alkaline phosphatase activity of lyophilized quality-control serum.

We studied the effectiveness of glycerol or ethylene glycol in preventing the increase in alkaline phosphatase activity of lyophilized or refrigerated quality-control serum after reconstitution or repeated freezing and thawing. Control serum reconstituted completely from the lyophilized state with subsequent storage at -20 degrees C showed a considerable decrease in alkaline phosphatase activit...

متن کامل

Profiling Glycated Hemoglobin Level, Lactate Dehydrogenase and Alkaline Phosphatase Activity in Gestational Diabetes Mellitus Obese Women and Compare Them with Each Other

Background and Aims: The aim of this study was profiling glycated hemoglobin (HbA1c) level, lactate dehydrogenase (LDH) and alkaline phosphatase (ALP) activity in obese women with gestational diabetes mellitus (GDM) and evaluating the correlation between them. Materials and Methods: Sample size was 90 subjects admitted to the clinical laboratory, who were divided into three groups, in each g...

متن کامل

An Alkaline Phosphatase Reporter Gene Assay for Induction of CYP3A4 In Vitro

CYP3A4 probably has the broadest catalytic activity of any cytochrome P450. It is a crucial task to test new drug candidates in a reliable system for their ability to induce expression of this enzyme. Firstly, a total of 300 bp core distal enhancer of CYP3A4 XREM region (-7972/-7673) were amplified from human genomic DNA. The PCR product was then ligated into a human secretory alkaline phosphat...

متن کامل

An Alkaline Phosphatase Reporter Gene Assay for Induction of CYP3A4 In Vitro

CYP3A4 probably has the broadest catalytic activity of any cytochrome P450. It is a crucial task to test new drug candidates in a reliable system for their ability to induce expression of this enzyme. Firstly, a total of 300 bp core distal enhancer of CYP3A4 XREM region (-7972/-7673) were amplified from human genomic DNA. The PCR product was then ligated into a human secretory alkaline phosphat...

متن کامل

ذخیره در منابع من


  با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید

برای دانلود متن کامل این مقاله و بیش از 32 میلیون مقاله دیگر ابتدا ثبت نام کنید

ثبت نام

اگر عضو سایت هستید لطفا وارد حساب کاربری خود شوید

عنوان ژورنال:
  • Clinical chemistry

دوره 18 12  شماره 

صفحات  -

تاریخ انتشار 1972