Short-term stability of free metanephrines in plasma and whole blood.
Author(s): Danese E, Montagnana M, Brentegani C, Lippi G
Publication: Clin Chem Lab Med, 2019, Vol. , Page
PubMed ID: 31348754 PubMed Review Paper? No
Purpose of Paper
This paper investigated the effects of delayed centrifugation and post-centrifugation storage of whole blood at room temperature or 4°C on levels of metanephrine and normetanephrine in plasma.
Conclusion of Paper
Plasma metanephrine and normetanephrine levels increased and then rapidly decreased when whole blood was stored at room temperature before or after centrifugation, but the decrease in metanephrine with post-centrifugation storage was not significant. Normetanephrine levels increased with pre- and post-centrifugation storage at 4°C, but metanephrine levels were unaffected.
Studies
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Study Purpose
This study investigated the effects of delayed centrifugation and post-centrifugation storage of whole blood at room temperature or 4°C on levels of metanephrine and normetanephrine in plasma. Whole blood from 10 healthy volunteers (6 females and 4 males) was collected into eight K2EDTA tubes. Two tubes were centrifuged immediately and the other three tubes were maintained at room temperature or 4°C for 1, 2, or 3 h before centrifugation. Plasma was then immediately frozen until analysis. Whole blood from 10 additional healthy volunteers (4 females and 6 males) was collected into K2EDTA tubes, immediately centrifuged, and then stored at room temperature or 4° for 0, 2, 4, or 6 h. Plasma was stored at −20°C until analysis measurement of metanephrine and normetanephrine levels by liquid chromatography tandem mass spectrometry (LC-MS/MS).
Summary of Findings:
Metanephrine and normetanephrine levels in plasma increased when whole blood was stored at room temperature before centrifugation after 1 h (P=0.039 and P<0.001, respectively) and then decreased after 2 h with levels of normetanephrine returning to baseline after 3 h (P=0.148) and metanephrine levels decreasing by 41% from baseline after 3 h (P<0.001). There were no significant differences in plasma metanephrine levels when blood was stored at 4°C before centrifugation but normetanephrine levels increased moderately after 3 h (P=0.007). Post-centrifugation storage of plasma at room temperature resulted in a decrease of metanephrine levels first observed after 4 h but differences did not reach statistical significance. Normetanephrine levels declined by 6% after 6 h of post-centrifugation storage of plasma at room temperature (P=0.018). Metanephrine was stable when plasma was stored for up to 6 h at 4°C after centrifugation, but normetanephrine levels increased ~4% from the baseline levels when plasma was stored for 6 h at 4°C (P=0.016).
Biospecimens
Preservative Types
- Frozen
Diagnoses:
- Normal
Platform:
Analyte Technology Platform Small molecule LC-MS or LC-MS/MS Pre-analytical Factors:
Classification Pre-analytical Factor Value(s) Biospecimen Aliquots and Components Centrifugation Centrifugation delays investigated
Storage Storage temperature Room temperature
4°C
Storage Storage duration 1 h pre-centrifugation
2 h pre-centrifugation
3 h pre-centrifugation
0 h post-centrifugation
2 h post-centrifugation
4 h post-centrifugation
6 h post-centrifugation
0 h pre-centrifugation
Storage Storage conditions Blood
Plasma