Impaired kidney function in rats six months after unilateral nephrectomy - an old story, a new perspective

Despite of routinely practised living kidney transplantation, data on consequences and impact of unilateral nephrectomy on the quality of life and health of donors are scarce. The aim of the present study was to examine long-term changes and function of the remnant kidney after unilateral nephrectomy in an animal model.

Thirty six female Sprague - Dawley rats at 4 months of age were randomized into the three groups: unilaterally nephrectomized, sham operated and naïve rats. The nephrectomy was done at inclusion in the experiment and their blood was taken at inclusion and six months thereafter.

There was a significant increase in serum creatinine concentrations six months after unilateral nephrectomy (39.7 ± 0.8 μmol/l) in comparison with the sham operated (30.1 ± 1.1 μmol/l) and the naïve rats (26.3 ± 3 μmol/l) (p ≤ 0.001). Serum sodium levels remained unchanged (p=0.116). Blood haemoglobin concentration did not differ between the three groups (p=0.115).

Although it has been very well established that kidney possesses huge capacity to compensate severe loss of renal mass, our results implicate that renal function undergoes significant deterioration with time after unilateral nephrectomy. Fortunately, in everyday clinical practice we do not see severe renal dysfunction in patients with a single kidney. However, prolongation of the human life span in the future could face us with renal impairment in living kidney donors. Future examination of specific biomarkers in our rat model (e.g. growth factors) could support our findings.