School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia.
School of Agriculture and Food Sciences, The University of Queensland, Gatton, Queensland, Australia.
J Vet Intern Med. 2019 Nov;33(6):2746-2751. doi: 10.1111/jvim.15629. Epub 2019 Oct 16.
Diseases associated with insulin dysregulation (ID), such as equine metabolic syndrome and pituitary pars intermedia dysfunction, are of interest to practitioners because of their association with laminitis. Accurate insulin concentration assessment is critical in diagnosing and managing these diseases.
HYPOTHESIS/OBJECTIVES: To determine the effect of time, temperature, and collection tube type on insulin concentrations in horses at risk of ID.
Eight adult horses with body condition score >6/9.
In this prospective study, subjects underwent an infeed oral glucose test 2 hours before blood collection. Blood samples were divided into ethylenediaminetetraacetic acid, heparinized, or serum tubes and stored at 4 or 20°C. Tubes were centrifuged and analyzed for insulin by a chemiluminescent assay over 8 days. Changes in insulin concentrations were compared with a linear mixed effects model.
An overall effect of time, tube type and temperature was identified (P = .01, P = 0.001, and P = 0.001, respectively). Serum and heparinized samples had similar concentrations for 3 days at 20°C and 8 days at 4°C; however, after 3 days at 20°C, heparinized samples had significantly higher insulin concentrations (P = .004, P = .03, and P = .03 on consecutive days). Ethylenediaminetetraacetic acid samples had significantly lower insulin concentrations regardless of time and temperature (P = .001 for all comparisons).
These results suggest an ideal protocol to determine insulin concentrations involves using serum or heparinized samples with analysis occurring within 3 days at 20°C or 8 days at 4°C.
与胰岛素失调（ID）相关的疾病，如马代谢综合征和垂体中间叶功能障碍，由于与蹄叶炎有关，因此引起了从业者的关注。准确评估胰岛素浓度对于诊断和治疗这些疾病至关重要。
假设/目的：确定时间、温度和采集管类型对处于 ID 风险中的马的胰岛素浓度的影响。
8 匹体况评分>6/9 的成年马。
在这项前瞻性研究中，研究对象在采血前 2 小时进行了口服葡萄糖试验。血液样本分为乙二胺四乙酸、肝素化或血清管，并在 4°C 或 20°C 下储存。管在 8 天内通过化学发光测定法离心并分析胰岛素。通过线性混合效应模型比较胰岛素浓度的变化。
确定了时间、管类型和温度的总体影响（P =.01、P = 0.001 和 P = 0.001，分别）。在 20°C 下 3 天和在 4°C 下 8 天，血清和肝素化样本的浓度相似；然而，在 20°C 下 3 天后，肝素化样本的胰岛素浓度显著升高（P =.004、P =.03 和 P =.03，连续几天）。无论时间和温度如何，乙二胺四乙酸样本的胰岛素浓度均显著降低（所有比较均为 P =.001）。
这些结果表明，确定胰岛素浓度的理想方案涉及使用血清或肝素化样本，在 20°C 下 3 天内或在 4°C 下 8 天内进行分析。
