Laboratory changes inherent to acute kidney injury induced by aminoglycosides in wistar rats

Abstract Acute kidney injury (AKI) is defined as an increase greater than 0.3 mg/L of serum creatinine within 48 hours and is a major cause of death in patients in intensive care units. Twenty-four Wistar rats were divided into three groups: Control (0.9% saline), Genta (gentamicin 50 mg.kg-1 BID) and Deh+Genta (gentamicin 50 mg.kg-1 BID + water restriction) and tested in an AKI model by aminoglycoside administration and dehydration implementation. The animals in the Deh+Genta group exhibited the lowest average weight and feed intake after the fifth day of the experiment. In this same period, water consumption by the Genta group was lower than the Control group, but in the following days of the experiment, polydipsia was noted for this group. The Deh+Genta group displayed the highest mean serum urea after the fifth day. The gentamicin-treated groups exhibited higher means than the Control group for serum creatinine, which proved to be a late renal marker for AKI. Serum GGT was higher in the Deh+Genta group, whereas urinary GGT was higher in the groups that received gentamicin, characterizing enzymuria, although severe dehydration can mask the results by indicating false negative values. The urinary GGT enzyme did not act as an early AKI biomarker. Decreased glomerular filtration rates enhanced the concentration of blood components and masked urinary and tissue components.

摘要 急性肾损伤（Acute kidney injury, AKI）被定义为48小时内血清肌酐升高超过0.3 mg/L，是重症监护病房患者死亡的主要诱因。本实验将24只Wistar大鼠分为三组：对照组（0.9%生理盐水）、庆大霉素组（庆大霉素50 mg·kg⁻¹ 每日两次，即BID）以及脱水+庆大霉素组（庆大霉素50 mg·kg⁻¹ 每日两次+限水），通过氨基糖苷类给药联合脱水构建AKI模型。实验第5天后，脱水+庆大霉素组的平均体重与摄食量均为各组最低；同期庆大霉素组的饮水量低于对照组，但实验后续天数中该组出现多饮现象。实验第5天后，脱水+庆大霉素组的平均血清尿素水平最高。庆大霉素处理组的血清肌酐水平均高于对照组，而血清肌酐被证实为AKI的晚发性肾脏标志物。脱水+庆大霉素组的血清γ-谷氨酰转移酶（Gamma-glutamyl transferase, GGT）水平更高，而接受庆大霉素的两组的尿GGT水平更高，此为酶尿症（enzymuria）的特征，但严重脱水可通过引发假阴性结果掩盖检测结果。尿GGT并未作为AKI的早期生物标志物发挥作用，肾小球滤过率降低会升高血液成分浓度，同时掩盖尿液及组织成分的水平变化。