rhodanine and rubeanic-acid

Six Merino sheep were dosed orally with a 0.2 per cent solution of copper sulphate, six others were undosed controls. Liver biopsies were obtained and stained for copper by the p-dimethylaminobenzylidene rhodanine (DMABR), rubeanic acid (RA) and ferricyanide (FCN) methods for examination by light microscopy. The initial and most marked accumulations of copper were found within the hepatocytes of the centrilobular zones. Increased copper loading resulted in copper deposition extending through the midlobular to the periportal zones. The deposition of copper was unequal between hepatocytes and with increasing copper loading isolated hepatocytes became packed with copper containing granules. Copper appeared within Kupffer cells and macrophages of portal triads. The first Kupffer cells to be positively stained and the greatest number of such cells were adjacent to the central veins. Accumulation of copper was demonstrated with hepatocytes at copper concentrations equivalent to 44.3 micrograms copper g-1 liver wet weight. The FCN method provided a more satisfactory demonstration of intracellular copper than the RA technique and the latter was better than the DMABR method. However, the DMABR technique provided the clearest morphological details.

Topics: Animals; Copper; Ferricyanides; Histocytochemistry; Liver; Rhodanine; Sheep; Staining and Labeling; Thioamides

Three different histochemical methods for copper detection were compared. Atomic absorption analysis was used to substantiate the tissue stains. There was good correlation between rhodanine staining and rubeanic acid-stained tissue sections. The orcein reaction for copper-associated protein did not consistently correlate with the methods demonstrating copper. Prolonged staining (72 hours) with rubeanic acid more consistently and clearly detected increased copper in canine livers than did staining with rhodanine. Seventy-two hour staining with rubeanic acid is the method of choice for histochemical detection of copper in canine liver.

Topics: Animals; Copper; Dog Diseases; Dogs; Female; Liver; Liver Diseases; Metallothionein; Oxazines; Rhodanine; Spectrophotometry, Atomic; Staining and Labeling; Thioamides