Diphenylamine-induced renal lesions in the chicken

Chronic intoxication with diphenylamine (DPA), which causes a cystic kidney disease in the rat and the guinea-pig, caused degeneration of the renal tubular epithelium in the chicken. This was similar to but much more serious than that preceding the formation of cysts in the rodents, but did not actually result in cyst formation, probably because of the high mortality rate observed in the birds even at this early stage. In the chicken until now it had been possible to obtain a pattern of renal cysts only with polychlorinated biphenyls (PCB) which also induce the "chick oedema" syndrome. The renal lesions due to DPA in the chicken were similar to those produced by PCB, but were not accompanied by oedema, which suggests that "chick oedema" caused by PCB is not due to renal insufficiency. The differences in the renal lesions noted in the various animal species give credit to the hypothesis that DPA may have two effects on the tubular epitelium, one stimulating cell proliferation and one leading to degeneration. Cysts may be formed only in those species in which there is cell proliferation.