Effectively simplified Adriamycin‐induced chronic kidney disease mouse model: Retro‐orbital vein injection versus tail‐vein injection

Abstract This study aimed to investigate the impact of administration routes in establishing the Adriamycin (ADR)‐induced chronic kidney disease (CKD) model. Using BALB/c mice, we compared the effects of conventional tail‐vein injection (TV10, 10 mg/kg) to those of retro‐orbital sinus (orbital vein) injection (OV10, 10 mg/kg; OV8, 8 mg/kg). The results indicated that the OV10 group exhibited CKD pathology similar to the TV10 group, with both groups demonstrating significantly higher urinary albumin/creatinine ratio ( p < 0.05), tubular injury ( p < 0.05), and degree of renal fibrosis ( p < 0.05) than the OV8 group. No significant differences were observed between the OV10 and TV10 groups in urinary albumin/creatinine ratio, tubular injury, and degree of renal fibrosis. These findings demonstrated that retro‐orbital administration of 10 mg/kg ADR induces comparable effects to conventional tail‐vein administration. This technique's technical simplicity may improve experimental efficiency, reproducibility, and animal welfare in CKD research. In conclusion, this study validates the utility of retro‐orbital injection in CKD model establishment, demonstrating its potential to standardize and improve the reliability of future CKD research protocols.