Toxic and immunodepressive effects of L-asparaginase from E. coli and from Erwinia carotovora following chronic administration in rats.

The effects of the administration of L-asparaginase from E. coli and Erwinia carotovora were studied in rats treated for 90 days with 800 or 3200 IU/kg body weight. The studies included overall toxicity on the liver, pancreas, and enteric mucosa as evaluated by both opitcal and electron microscopic examination, biochemical findings, behaviour of IgM-hemolysin producing cells, and antias-paraginase antibody production. The toxic effect and the immunodepressive activity appeared rather early, tending later to decrease. No sex correlation or clear cut dose correlation were observed. However, slight differences in toxicity between the two types of L-ASN-ase were present.