Intracerebroventricular administration of BaCl2 was found to produce severe, fatal convulsions in male Swiss-Webster mice with an LD50 (95% C.L.) at 10 min postadministration of 0.597 (0.395–0.901) ?mol/mouse. Antagonism of BaCl2-induced convulsions and lethality was obtained with pretreatment of atropine (1 to 5 mg/kg, ip) or naloxone (1 to 5 mg/kg, sc). A multivariate logistic model was used to examine the effect of atropine and naloxone on BaCl2 lethality. Atropine was found to be significantly more efficacious than naloxone in antagonizing BaCl2 lethality.
Antagonism of barium chloride lethality by atropine and naloxone: analysis by a multivariate logistic model