Liver and kidney lesions and associated enzyme changes induced in rabbits by chronic cyanide exposure

The effect of prolonged chronic cyanide exposure on liver and kidney integr ity, as well as some associated enzyme and metabolite changes, were investi gated in New Zealand white rabbits (initial mean weight 1.52 kg) using a co mbination of colorimetric, spectrophotometric, enzymatic, gravimetric and h istological procedures. Two groups of rabbits were fed for 40 weeks on eith er pure growers' mash or growers' mash containing 702 ppm inorganic cyanide . Results obtained indicate that the cyanide-fed rabbits had significantly decreased liver activities of alkaline: phosphatase, glutamate pyruvate tra nsaminase and sorbitol dehydrogenase relative to controls (P < 0.05). On th e other hand, there were significant increases (P < 0.05) in the serum acti vities of these enzymes in the cyanide-treated group. Kidney alkaline phosp hatase activity was significantly decreased (P < 0.05), while serum urea an d creatinine were significantly higher (P < 0.05) in the cyanide group rela tive to controls. The cyanide treatment led to significant increases in bot h tissue and serum activities of lactate dehydrogenase. In addition, liver and kidney rhodanese activities were significantly raised in the cyanide-fe d group. There were marked degenerative changes in the liver and kidney sec tions front the cyanide-treated rabbits. These results suggest that chronic cyanide exposure may be deleterious to liver and kidney functions. (C) 199 9 Elsevier Science Ltd. All rights reserved.