Table 1.
Summary of Incidence and Severity of Rat Kidney Lesions after 28-day Exposure to Diet Containing 0 (control group), 120, 180, or 240 ppm of MEL and CYAa
| Dose group (ppm of MEL and CYA in feed) | 0 | 120 | 180 | 240 | ||||
| Sex | M | F | M | F | M | F | M | F |
| Crystals | 0b | 0 | 87 | 37 | 75 | 75 | 100 | 100 |
| Dilatation, renal tubule | 0 | 0 | 0 | 0 | 75 (2.4) | 25 (2.0) | 100 (4.0) | 100 (3.7) |
| Fibrosis | 0 | 0 | 0 | 0 | 12 (2.0) | 0 | 50 (3.2) | 50 (2.5) |
| Regeneration, renal tubule | 87 (1.0) | 37 (1.0) | 87 (1.1) | 50 (1.0) | 100 (2.5) | 100 (1.9) | 100 (4.0) | 100 (3.7) |
| Necrosis, renal tubule, epithelium | 0 | 0 | 0 | 0 | 25 (1.0) | 0 | 100 (2.2) | 100 (1.8) |
| Infiltration cellular, lymphocyte | 0 | 0 | 0 | 0 | 37 (1.0) | 25 (1.0) | 37 (2.0) | 37 (1.6) |
| Hyperplasia, pelvis, transitional epithelium | 0 | 0 | 12 (2) | 0 | 12 (3) | 12 (2) | 87 (2.0) | 100 (1.6) |
aData are from Gamboa da Costa et al. (forthcoming) and represent 8 rats per dose group used for urinary biomarker analysis. Kidney lesion severity values for individual rats are provided in Supplementary table 2.
b% incidence; severity value in parentheses: 0, not observed; 1, minimal; 2, mild; 3, moderate; 4, marked.