MAGNESIUM LITHOSPERMATE-B SUPPRESSES THE INCREASE OF ACTIVE OXYGEN INRATS AFTER SUBTOTAL NEPHRECTOMY

Subtotally nephrectomized rats were found to have decreased activities of superoxide dismutase (SOD) and catalase, and spin trapping with 5, 5-dimethyl- pyrroline-N-oxide (DMPO) showed that the amount of hydroxy l radical in the residual kidney tissue was greater than that in norma l rat kidney. This indicated both direct and indirect involvement of f ree radicals in renal failure. In contrast, rats given magnesium litho spermate B (10 mg/kg body weight) orally for 30 days after subtotal ne phrectomy showed restoration of SOD and catalase activities to almost normal levels. Hydroxyl radical, which is highly reactive and for whic h there is no scavenger system in the body, was decreased markedly in kidney homogenates obtained from rats given magnesium lithespermate B and in an experimental system for hydroxyl radical production to which magnesium lithospermate B was directly added. The increased levels of uremic toxins in the blood were also low in rats given magnesium lith ospermate B. This indicates that magnesium lithospermate B helps to in hibit the progression of renal failure by scavenging radicals.