EFFECTS OF Zn-DTPA ON ESSENTIAL TRACE METALS IN RATS

Zn-DTPA was injected intraperitoneally into rats (30 µmol/kg) with a single dose or a daily dose for 10 consecutive days. Urine samples were collected for 24 hours after the single injection and tissue samples were excised 20 hours after the final of the consecutive injections. Elements in these samples were analyzed by PIXE. Zn-DTPA raised the urinary concentration of zinc and copper, and their urinary losses caused by Zn-DTPA were estimated to be 1.9 and 0.01 mg/30μmol Zn-DTPA, respectively. The concentration of metals in the liver, kidneys, brain and femurs remained unchanged. These results suggest that almost all of Zn-DTPA is excreted into the urine without replacement with other metals, and so this chelating agent may not induce any deficiencies of essential metals when animals are treated with a dose of 30 µmol/kg per day.