Kinetics of the expressions of radiation-induced plasma proteins of the cardiac territory in electrophoresis

ABSTRACT Introduction: Radiation induces acute and late alterations in blood proteins. Objective: The present study aims at analyzing in time kinetics the electrophoretic profiles of expression bands of blood protein, in the molecular weight range greater than and equal to that of albumin, modulated by ionizing radiation in the cardiac territory, in animal model. Material and methods: Animals were exposed to a whole-body dose of 5 Gy ionizing radiation (Co-60). Serum samples were collected from isogenic Wistar rats (control and irradiated groups). At a time kinetics of 12, 24, 48, 72, 96 hours and 35 days post-irradiation, thoracolaparotomies were performed with anesthesia, and 0.3 ml of blood was collected between the left ventricle and the pulmonary artery. The samples were held in heparin and their components were separated by centrifugation. Protein bands with similar molecular weight were identified by vertical 10% electrophoresis, silver staining. Results: The findings indicate a systemic acute altered expression of proteins with molecular weight greater than or equal to that of albumin in acrylamide gel, presenting suppression and increased expression due to modulation of preexisting bands, identified in time kinetics. Conclusion: These findings point out to acute alterations of protein expression modulated in time, but also to a late modulation of gene expression.

摘要
引言：辐射可诱导血液蛋白质产生急性与晚期的改变。
研究目的：本研究以动物模型为对象，旨在分析电离辐射作用于心脏区域后，分子量不低于白蛋白的血液蛋白表达条带的电泳图谱的时间动力学变化。
材料与方法：实验动物分为对照组与照射组，均采用同基因系Wistar大鼠。受试动物接受全身剂量为5 Gy的电离辐射（钴-60源）。分别于照射后12、24、48、72、96小时及35天开展采样：对处于麻醉状态的大鼠实施胸腹联合切开术，于左心室与肺动脉之间采集0.3 mL血液。血液样本以肝素抗凝，经离心分离血清组分。采用10%垂直电泳结合银染法，对分子量不低于白蛋白的蛋白质条带进行鉴定。
结果：研究结果显示，在聚丙烯酰胺凝胶中，分子量不低于白蛋白的蛋白质出现全身性急性表达异常，表现为原有条带的表达受辐射调控后呈现表达抑制与上调，且该变化具有时间动力学特征。
结论：上述结果表明，蛋白质表达的急性改变存在时间依赖性的调控特征，同时也存在基因表达的晚期调控效应。