Experimental chronic copper toxicity in sheep. Histological and histochemical changes during the development of the lesions in the liver
Ishmael, J.; Gopinath, C.; Howell, J.M.
Research in Veterinary Science 12(4): 358-366
1971
ISSN/ISBN: 0034-5288 PMID: 4254224 Document Number: 37131
Histological and histochemical changes in the livers of 8 sheep given continuous doses of copper sulphate were studied in serial needle biopsy samples. Necrosis of isolated parenchymal cells and occasional swollen PAS-positive, diastase-resistant, copper-containing Kupffer cells, rich in acid phosphatase, were seen in samples taken some 6 weeks before the haemolytic crisis. In subsequent samples, isolated parenchymal cell necrosis became more widespread, swollen Kupffer cells were more numerous and tended to occur in clusters. Many parenchymal cells appeared swollen and showed fatty change, karyomegaly and nuclear vacuolation. In samples taken at the time of the haemolytic crisis, extensive focal necrosis of liver tissue was seen. In animals which had survived a haemolytic episode, large amounts of bile pigment were present in canaliculi and small bile ducts, and periportal fibrosis occurred. The reduction in activity of the hydrolytic enzymes adenosine triphosphatase and non-specific esterase and of the oxidative enzymes succinic dehydrogenase and glutamic dehydrogenase seen in the first port-dosing samples became progressively more severe. Gross and microscopic lesions found at post-mortem examination are described, and attention is drawn to the status spongiosus in the white matter of the central nervous system.