Fyhrquist F, Puutula L
Clin Chem. 1978 Jul;24(7):1202-4.
Plasma renin activity was measured in parallel in Na2EDTA-contained plasma samples after storage at -20, 4, and 24 degrees C, and in the lyophilized state. In peripheral venous plasma from 22 hypertensive patients, the activity (range, 0.08-46.7 microgram/liter per hour) remained stable during three days of storage at 4 degrees C, but decreased to a variable extent when plasma was kept at 24 degrees C: in one day by 9.2%, two days by 25.6%, and three days by 74.0%. Values were the same for samples handled at room temperature and chilled to 4 degrees C within 3 h and parallel samples immediately cooled in an icebath and kept at 4 degrees C. Freezing (-20 degrees C) and thawing of plasma was associated with a 22% mean increase in activity (range, 0-83%). Lyophilization resulted in a smaller increase of plasma renin activity (mean 12%, range 0-46%). Blood for renin analysis need not be cooled immediately, but must be cooled to 4 degrees C within 2-3 h. It then is stabe for at least three days. Freezing or lyophilization appears to be associated with some cold activation of "prorenin."
在含有乙二胺四乙酸二钠（Na2EDTA）的血浆样本中，分别于-20℃、4℃和24℃储存以及处于冻干状态下平行测定血浆肾素活性。在22例高血压患者的外周静脉血浆中，活性（范围为0.08 - 46.7微克/升·小时）在4℃储存三天期间保持稳定，但当血浆置于24℃时会有不同程度下降：一天下降9.2%，两天下降25.6%，三天下降74.0%。对于在室温下处理并在3小时内冷却至4℃的样本以及立即在冰浴中冷却并保持在4℃的平行样本，其值相同。血浆冷冻（-20℃）和解冻后活性平均增加22%（范围为0 - 83%）。冻干导致血浆肾素活性增加幅度较小（平均12%，范围为0 - 46%）。用于肾素分析的血液不必立即冷却，但必须在2 - 3小时内冷却至4℃。然后它至少可稳定三天。冷冻或冻干似乎与“肾素原”的某种冷激活有关。
