Mercuric chloride-induced renal tubular necrosis in the rat.

A light microscopic study of the renal tubulonecrotic lesion in rats given a small dose of HgCl2 is described. The changes consist of a rapidly developing vacuolation of the cytoplasm with loss of basophilic staining within 4 h that leads to cell breakdown, fragmentation and dissolution by 48 h. Nuclear changes appear to set in later. Permanent patchy fibrotic lesions were found in the kidneys at 10 days. The animals pass a large amount of urine of low osmolarity, low Na+, K+ and Cl- for a period of 3 days accompanied by an increased water intake. Nevertheless there appeared to be no water or ionic imbalance between daily inputs and outputs. Blood urea levels were greatly increased for 3 days, but did not return to normal by the 10th day.