Influence of Diet and Strain of Rat on Kidney Damage Observed in Toxicity Studies

Abstract

The laboratory animal is susceptible to biological variation due to a variety of causes. Thus genetic variation and nutrition have become recognized to influence the reaction of the animal to experimental procedures.

Severe kidney injury was observed at our institute in preliminary studies with 1% butylated hydroxy toluene (BHT) incorporated in a semisynthetic diet fed to Wistar rats for one month. These lesions together with nephrocalcinosis, a common finding in rats fed a semisynthetic diet might suggest that the animals in our experiment were predisposed to kidney damage.

In order to show the influence of the rat strain and the type of diet a study was performed with both Wistar and Sprague-Dawley rats fed a semisynthetic or commercial diet mixed with 1% BHT. It was observed that the semisynthetic diet had a marked effect on the severity of the kidney lesions and that the lesions were independent of the rat strain used.

In addition, an apparent sex variation was found.