The effects of repeated administration of various chelating agents on the removal of strontium from the mouse.

The effects of repeated ip administration of diethylenetriaminepentaacetic acid (DTPA), Kryptofix 222, 1,4,7,10,13,16-hexaoxacyclooctadecane (18-crown-6), ethylenglycol-bis-(beta-amino-ethylether)-N,N'-tetraacetic acid (EGTA), and Kryptofix 5 on the distribution and excretion of sc-injected strontium were investigated in male Swiss mice. Groups of 20 animals received 95 mg strontium nitrate/kg, and 10 min later ip treatment with one of the chelators or 0.9% saline was initiated and continued for 10 d. The animals were housed in plastic metabolism cages, and urine and feces were collected daily during the period of treatment. At the end of this period, the animals were killed and the concentration of strontium determined in their tissues. Only Kryptofix 5 and EGTA significantly increased the amount of strontium excreted into feces, whereas none of the chelators significantly enhanced the urinary elimination of strontium. Treatment with Kryptofix 5 significantly decreased the concentration of strontium in all tissues analyzed. Kryptofix 5 was the most effective agent of those tested in the removal of strontium after a single dose of strontium nitrate.