TOXICITY OF STRYCHNINE TO THE RAT. 



5 



does not necessarily signify a protracted period of danger or a 

 marked increase in susceptibility of the individual to immediate sub- 

 sequent poisoning. Hatcher and Eggleston (11), who have shown 

 that the protective mechanism of the animal consists chiefly in the 

 ability of the organism quickly to destroy this drug within the 

 tissues, found the following coefficients of disposal, which are ex- 

 pressed in terms of the percentage per hour of a minimum subcuta- 

 neous lethal dose : For the cat, 12 to 25 ; for the dog, 14 to 17 ; and for 

 the guinea pig, 18 to 57. These coefficients represent the conditions 

 found when the strychnine is maintained somewhere in the neigh- 

 borhood of the lethal concentration and not absolute hourly decre- 

 ments when only a single' subcutaneous lethal dose is given. 



Under ordinary circumstances, in case of survival of the animal, 

 strychnine is completely absorbed from the gastro-intestinal tract 

 (12), but the exact role played by the stomach has not yet been 

 determined. Although this organ is not endowed with general 

 absorptive properties, it has been shown (22) that strychnine can 

 be absorbed from the mucosa of Pawlow stomach fistulse in dogs. 

 However, a fatality from the administration of the minimum oral 

 lethal dose of strychnine to an animal, such as a dog or cat, which 

 usually has an empty stomach, in which the absorption of the entire 

 dose is through the stomach mucosa, remains to be demonstrated. 

 Nevertheless, it is possible that the absorption of the effective portion 

 of the dose may occur in some instances chiefly or entirely through 

 the gastric mucosa, particularly when the dose is very large. 



Table 2. — Relation of the oral to the subcutaneous lethal dose of strychnine 



sulphate. 



Animal. 



Oral 



lethal dose 



per kilo. 



Subcuta- 

 neous 

 lethal dose 

 per kilo. 



Ratio. 



Citation. 



Ouinea pig 



Milligrams. 

 144.0 



Milligrams. 

 14.4 



3 10 to 1 



7tol 



2 1.20 to 1 



1.20 to 1 



<5tol 



Hatcher and Eggleston (11). 

 Nobecourt (18). 



Rabbit 



Cat 



M.48 

 2 5.4 



2 3.84 

 24.6 



Hatcher and Eggleston (11). 



Dog 



Do. 





S. E. Piper (17). 









1 Calculated from authors' data (Table 1). 



2 Calculated from authors' data, 0.0128 per cent strychnine sulphate solution used (Table 1). 



3 Approximate. 



4 Stomach to cheek-pouch ratio for poisoned grain. 



In animals which can be obtained with empty stomachs, such as 

 the cat and dog, the ratio of the oral lethal dose to the true species 

 tolerance is very small, whereas in rabbits and guinea pigs, which 

 have food continuously present in the stomach, it is extremely high. 

 Presumably the rat would fall automatically into the second class, as 

 the poison is to be administered in the food. This extreme point of 



