Sulfonamide Drugs as Protective Agents Against Carbon Tetrachloride Poisoning. ∗

During the last few years we have been interested in the mechanism whereby the subcutaneous injection of various substances such as xanthine, sodium ricinoleate, etc., increases a rat's resistance to the poisonous action of carbon tetrachloride or chloroform. During the course of this investigation, we were led to try the possible effect of oral administration of sulfanilamide on the animal's resistance to carbon tetrachloride. To our considerable surprise, it was found to reduce the mortality rate very markedly. Later experiments confirmed this finding and showed that orally administered sulfanilamide exerted a definite protective action against liver necrosis from acute carbon tetrachloride poisoning.

Experimental. Male and female rats, weighing from 200 to 300 g were used. In the individual experiments animals of the same sex and of approximately the same weight were used for control and treated animals. In the experiments recorded in Table I, the sulfonamide drugs were given by stomach tube in doses of 30 mg per 100 g of body weight. Two doses, one 20 hours, the other 3 hours before the time of acute poisoning, were administered. A few preliminary experiments were carried out with sulfanilamide in doses of 10 and 15 mg per 100 g of body weight. The degree of protection was apparently less than that with the higher doses, consequently the other drugs were not studied at the lower levels. The method of anesthesia was the same as described in a previous article. 1 In the experiments recorded in Table I, mortality alone has been considered as the evidence of protection. Similar experiments, however, have been carried out, involving 18 controls and 22 sulfanilamide-treated animals, in which the duration of anesthesia was reduced so that most of the control animals survived.