3.1 Assessment of renal injury
The extent of injury caused by cisplatin treatment was assessed in both mouse strains by plasma creatinine levels (Figure 1A and 1C ) and histological evaluation by a clinical pathologist (Figure 1B and 1D ). Plasma creatinine concentrations were 4.3-fold and 5.4-fold higher in day 4 cisplatin-treated C57BL/6 and FVB/N mice, respectively, compared to day 4 saline controls (p<0.05). In day 3 cisplatin-treated C57BL/6 and FVB/N mice, plasma creatinine concentrations were increased 2.3-fold and 2.0-fold compared to saline controls, although this difference was not statistically significant. In day 3 cisplatin-treated mice, 3/9 (33%) C57BL/6 mice and 5/8 (62.5%) FVB/N mice showed signs of histological renal injury (injury score ≥ 1), whereas on day 4, histological damage was observed in 6/8 (75%) and 5/7 (71.4%) cisplatin-treated C57BL/6 and FVB/N mice, respectively. Histological injury was not observed at any other timepoint, with the exception of one C57BL/6 mouse in the day 1 cisplatin group (1/9, 11.1%).