Shigeo Hokari

The effect of copper on intact swine erythrocytes

The effect of copper on intact swine erythrocytes was investigated in vitro. When treated with copper, a decrease in the GSH content, accumulation of copper in the cell, loss of potassium and gain of sodium, cross-linking of membrane proteins and echinocytic transformation were observed. All of these phenomena seem to be caused by a potent oxidant action of copper. These cytotoxic effects of copper were markedly inhibited by the addition of bovine serum albumin in the incubation medium. These results may help to understand the mechanism of hemolysis associated with copper poisoning in vivo.

Lipid Peroxide in Dog Foods

(4•Ž) or a darkroom, and exposed to a fluorescent light or the sun, and changes in the lipid peroxide concentration were examined in each of the dog foods for 30 days. The concentrations in dog foods exposed to a original light and the sun increased to 350-630% and 700-2100% of the original value, respectively, after 30 days. The dog foods kept in a refrigerator or a darkroom, however, showed only a slight increase in concentration. To inhibit the increase in lipid peroxide concentration, it seems desirable to keep dog foods in a refrigerator or a darkroom. ―J. Jpn. Vet. Med. Assoc., 42, 239•`243 (1989).

Isoelectric focusing of nonspecific esterases in polyacrylamide microgels.

A method is described for isoelectric focusing of murine nonspecific esterases on polyacrylamide gel using hematocrit capillary tubes. For an analysis, less than 50μg of mouse tissues and only 30μl of gel mixture were needed. And it required only about two hours for a complete analysis. Using this method to analyze nonspecific esterases extracted from mouse tissues, it was possible to identify a composite total of 31 bands of nonspecific esterases.

Effect of phenobarbital on the absorption of copper by rat small intestine.

The effect of Phenobarbital (20, 40 and 80 mg/kg/day intraperitoneally for 5 days) on the absorption of copper from the rat small intestine was studied using an in situ recirculation technique. In untreated animals 45.7% of the initial amount of copper was absorbed after a 90-min recirculation. The pretreatment with phenobarbital resulted in a significant increase in the absorption of copper and at the end of 90 min of recirculation 56.7%, 62.7% and 70.0% of the initial amount were absorbed in the animals treated with phenobarbital at the dosages of 20, 40 and 80 mg/kg, respectively. To determine the absorption of copper from different sites of the small intestine, the intestine was divided into three segments of duodenum, jejunum and ileum. The copper absorption varied markedly in different segments and was the largest in duodenum followed in order of jejunum and ileum. Phenobarbital treatment resulted in a marked increase in the copper content in duodenum and jejunum as well as liver and kidney. Together with previous informations, the present data suggest that the phenobarbital-mediated increase in the copper absorption is related to increased synthesis of a carrier protein which may be involved in copper transport.