Look at Table 2: for the “Vehicle” group (which got only CMC and gentamicin), the urea level is 42.81 ± 4.66 mg/dL.
Now, go to the results section for cadmium (Section 3.3): the control group there had a urea of 41.27 mg/dL, which makes sense because CdCl₂ is nephrotoxic.
The problem? The paper says gentamicin was given as a single 100 mg/kg dose (Section 2.11). That’s an extremely high, acutely toxic dose. It should cause much worse kidney damage than cadmium chloride (3 mg/kg/day for 4 days).
But the data shows gentamicin caused less urea elevation (42.81) than cadmium (41.27)? That doesn’t add up. A single 100 mg/kg gentamicin dose should push urea way higher, like into the 70-100+ mg/dL range based on standard models.
So the reported value in Table 2 is too low to be credible for that dose. Either the dose wasn’t actually given as described, or the data is wrong. Either way, it undermines the whole gentamicin part of the study.