CHRONIC INTOXICATION RABBITS. 



69 



TABLE 17. Chronic intoxication of rabbits, series B, Group IV, on cumulation Contd. 



RABBIT, 371. 



SERIES C. 

 / 



The subjects used in these experiments were rabbits of medium size and were appar- 

 ently young or at any rate were not very old. The series was planned for the study 

 of the possible effect of diet on the toxicity of caffein when given for some time, and 

 therefore oats were substituted for carrots, which had been fed in the previous work, as 

 already stated. Caffein was given by mouth in the usual way, in 1 per cent solution, 

 100 nag. per kilo daily. ' Fourteen rabbits were used for these tests. Their weights were 

 recorded daily and observations made at frequent intervals during the day. 



The only change noticed in all of the experiments of this series was progressive loss 

 of weight which set in from 3 to 8 days after the administration of the drug was begun. 

 The duration of life varied considerably. No. 382 died after the first dose. No. 389 

 lived 2 days, No. 386, 3 days, and No. 385, 5 days; No. 390 lived 7 days and -No. 404 

 lived 20 days after the administration of caffein was begun. The duration of life in all 

 the others was from 11 to 16 days. The findings at autopsy are interesting and suggestive 

 as regards the possible explanation of the effects of repeated dosage of caffein. In eight 

 of the rabbits there was involvement of the mucous membrane of the stomach or intes- 

 tines or of both. Since the same condition of the gastro-intestinal canal was observed 

 in previous experiments with caffein when injected subcutaneously, the mere passing 

 of the tube into the stomach is obviously not the cause of this condition. The fatal 

 outcome due is therefore, as was suggested above, to inanition brought about by the 

 condition of the gastro-intestinal canal. Moreover parallel experiments carried out 

 on rabbits in the same way with alcohol survived this treatment much longer. 

 Obviously then the passing of the soft rubber catheter is not the cause of this condition 

 of the gastro-intestinal canal nor the diet. Rabbits were fed oats exclusively for several 

 months in this laboratory and thrived. The presence of pneumonia in the other 

 rabbits of this series may be regarded as accidental, as it is inconceivable that one or 

 two doses of caffein, as was the case in Nos. 382 and 389, could predispose the lungs to 

 infection. The results of these experiments therefore are in harmony with those of 

 the preceding two series, indicating that caffein does not accumulate in the body , and 

 that the toxicity of caffein, whether of the single dose or of repeated doses is the same, 



