EFFECTS OF DIETARY ZINC RESTRICTION ON BISMUTH INDUCTION OF RAT-KIDNEY METALLOTHIONEIN

Bismuth-stimulated elevation of metallothionein levels is proposed to inhibit side effects of chemotherapy drugs such as cisplatin and adria mycin. In the present study, low zinc intake by rats limited bismuth-i nduced accumulation of renal metallothionein protein, and metallothion ein-associated zinc and bismuth. In contrast, bismuth strongly elevate d metallothionein mRNA in rats fed low zinc. Thus, bismuth does not ap pear to require zinc to stimulate high metallothionein mRNA accumulati on, bur seems to need this metal to accumulate metallothionein protein . Therefore, the efficacy of bismuth in restricting chemotherapy drug side effects in humans may depend on the zinc status of the people und er treatment.