Effect of age, clonidine or propranolol on behavioral toxicity induced with digitoxin in mice.

In three experiments, behavioral toxicity induced by 5 different dose levels of digitoxin was investigated in mice that were treated with either clonidine or propranolol or were either young (70-140 days), middle aged (240-260) or old (450-600). Observed on four drug-induced behavior categories, it was found that both clonidine and propranolol attenuated the toxic effects of relatively low dose levels of digitoxin, while at higher digitoxin dose levels only propranolol was able to reduce significantly the ED50 and the LD50. The results were discussed in terms of adrenergic mechanisms mediating digitoxin toxicity. Aged mice were found to be the least and middle aged the most resistant to the toxic effects of digitoxin.