Abstract
This study was performed to determine the effect of frozen and unfrozen storage on plasma high density lipoprotein (HDL) cholesterol analysis. HDL-cholesterol was determined, following removal of the other lipoproteins by precipitation with heparin and MnCl 2, in fresh plasma samples and in aliquots of the samples that had been stored 1) unfrozen (4°C), up to 14 days, 2) frozen (-20°C), up to 14 days, and 3) frozen (-20°C), 5-6 years. There were progressive changes in measured HDL-cholesterol values under all conditions of storage. The changes were significantly and most highly correlated with HDL-cholesterol level and they reached about 4 mg/dl for each 10 mg/dl initial HDL-cholesterol concentration. Samples with low HDL-cholesterol concentrations tended to increase with storage, and those with high HDL-cholesterol levels tended to decrease. Since the changes were in opposite directions, the group means tended to be preserved. The mean differences between fresh and stored samples were (stored-fresh): 1-14 days, 4°C, -0.10 to +4.60 mg/dl; 1 hour-14 days, -20°C, +0.80 to 1.92 mg/dl; 5-6 years -20°C, -1.92 mg/dl. Values changed most rapidly during storage at 4°C and were accompanied by changes in the precipitability of the lipoproteins; low density lipoproteins became progressively difficult to precipitate completely, and HDL became progressively easier to precipitate. The measured HDL-cholesterol level depends on which process predominates and can lead to grossly inaccurate measurements, particularly at the extremes of HDL-cholesterol concentration.
| Original language | English (US) |
|---|---|
| Pages (from-to) | 608-616 |
| Number of pages | 9 |
| Journal | Journal of Lipid Research |
| Volume | 21 |
| Issue number | 5 |
| State | Published - 1980 |
| Externally published | Yes |
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ASJC Scopus subject areas
- Endocrinology
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Determination of high density lipoprotein-cholesterol in stored human plasma. / Bachorik, P. S.; Walker, R.; Brownell, K. D.; Stunkard, A. J.; Kwiterovich, P. O.
In: Journal of Lipid Research, Vol. 21, No. 5, 1980, p. 608-616.Research output: Contribution to journal › Article
}
TY - JOUR
T1 - Determination of high density lipoprotein-cholesterol in stored human plasma
AU - Bachorik, P. S.
AU - Walker, R.
AU - Brownell, K. D.
AU - Stunkard, A. J.
AU - Kwiterovich, P. O.
PY - 1980
Y1 - 1980
N2 - This study was performed to determine the effect of frozen and unfrozen storage on plasma high density lipoprotein (HDL) cholesterol analysis. HDL-cholesterol was determined, following removal of the other lipoproteins by precipitation with heparin and MnCl 2, in fresh plasma samples and in aliquots of the samples that had been stored 1) unfrozen (4°C), up to 14 days, 2) frozen (-20°C), up to 14 days, and 3) frozen (-20°C), 5-6 years. There were progressive changes in measured HDL-cholesterol values under all conditions of storage. The changes were significantly and most highly correlated with HDL-cholesterol level and they reached about 4 mg/dl for each 10 mg/dl initial HDL-cholesterol concentration. Samples with low HDL-cholesterol concentrations tended to increase with storage, and those with high HDL-cholesterol levels tended to decrease. Since the changes were in opposite directions, the group means tended to be preserved. The mean differences between fresh and stored samples were (stored-fresh): 1-14 days, 4°C, -0.10 to +4.60 mg/dl; 1 hour-14 days, -20°C, +0.80 to 1.92 mg/dl; 5-6 years -20°C, -1.92 mg/dl. Values changed most rapidly during storage at 4°C and were accompanied by changes in the precipitability of the lipoproteins; low density lipoproteins became progressively difficult to precipitate completely, and HDL became progressively easier to precipitate. The measured HDL-cholesterol level depends on which process predominates and can lead to grossly inaccurate measurements, particularly at the extremes of HDL-cholesterol concentration.
AB - This study was performed to determine the effect of frozen and unfrozen storage on plasma high density lipoprotein (HDL) cholesterol analysis. HDL-cholesterol was determined, following removal of the other lipoproteins by precipitation with heparin and MnCl 2, in fresh plasma samples and in aliquots of the samples that had been stored 1) unfrozen (4°C), up to 14 days, 2) frozen (-20°C), up to 14 days, and 3) frozen (-20°C), 5-6 years. There were progressive changes in measured HDL-cholesterol values under all conditions of storage. The changes were significantly and most highly correlated with HDL-cholesterol level and they reached about 4 mg/dl for each 10 mg/dl initial HDL-cholesterol concentration. Samples with low HDL-cholesterol concentrations tended to increase with storage, and those with high HDL-cholesterol levels tended to decrease. Since the changes were in opposite directions, the group means tended to be preserved. The mean differences between fresh and stored samples were (stored-fresh): 1-14 days, 4°C, -0.10 to +4.60 mg/dl; 1 hour-14 days, -20°C, +0.80 to 1.92 mg/dl; 5-6 years -20°C, -1.92 mg/dl. Values changed most rapidly during storage at 4°C and were accompanied by changes in the precipitability of the lipoproteins; low density lipoproteins became progressively difficult to precipitate completely, and HDL became progressively easier to precipitate. The measured HDL-cholesterol level depends on which process predominates and can lead to grossly inaccurate measurements, particularly at the extremes of HDL-cholesterol concentration.
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UR - http://www.scopus.com/inward/citedby.url?scp=0019217462&partnerID=8YFLogxK
M3 - Article
C2 - 7400691
AN - SCOPUS:0019217462
VL - 21
SP - 608
EP - 616
JO - Journal of Lipid Research
JF - Journal of Lipid Research
SN - 0022-2275
IS - 5
ER -