Renin-Angiotensin-Aldosterone System (RAAS) measurements are influenced by several factors. We investigated the effect of sample delivery conditions on RAAS measurements including sample storage temperature and time. Blood samples were collected from thirty participants using enzyme inhibitor tubes and serum separation gel evacuated tubes. Plasma and serum from fresh blood samples without further storage (as baseline), and from blood samples that were stored at either 0 °C, 4 °C, or 25 °C for 3 h, 6 h and 24 h, respectively, were extracted and stored at −30 °C for batch measurements using radioimmunoassay. Concentrations of Aldosterone (Ald) decreased following delivery temperature and time, and were significantly different when samples were set aside at 0 °C for 24 h (p < .01), 4 °C for 6 h (p < .01), and 25 °C for 3 h (p < .05). However, levels of Angiotensin (Ang I) increased following delivery temperature and time, and were significantly different when samples were set aside at 0 °C and 4 °C for 6 h (p < .05) and at 25 °C for 3 h (p < .001). However, no changes were observed for the concentrations of plasma renin activity (PRA) and Ang II, except for Ang II which increased significantly when samples were set aside at 25 °C for 24 h (p < .001). Our results indicate that samples used for RAAS measurement should be placed at a low temperature and analyzed as soon as possible after collection.

肾素-血管紧张素-醛固酮系统（RAAS）的测量受多种因素影响。我们调查了样品传送条件对RAAS测量的影响，包括样品存储温度和时间。使用酶抑制剂管和血清分离凝胶真空管从三十名参与者中采集血液样本。从没有进一步存储（作为基准）的新鲜血液样本中以及分别在0°C，4°C或25°C下存储3 h，6 h和24 h的血液样本中提取血浆和血清并储存在−30°C下，以进行放射免疫测定。醛固酮（Ald）的浓度随递送温度和时间的延长而降低，当样品分别在0°C放置24 h（p  <.01），4°C放置6 h（p <.01），并在25°C下放置3小时（p  <.05）。然而，血管紧张素（血管紧张素I）的水平增加以下输送温度和时间，并且是显著不同样品时，在0℃和4℃下6小时（分别搁置p  <0.05），并在25℃下保持3小时（p  <.001）。但是，血浆中的肾素活性（PRA）和Ang II的浓度没有变化，只有Ang II在25°C放置24 h时会显着增加（p  <.001）。我们的结果表明，用于RAAS测量的样品应置于低温下，并在收集后尽快进行分析。