TETANUS TOXINES. 363 



and Doyon. A dog received a certain dose of toxine, and 

 after tetanic symptoms had arisen, direct transfusion of its 

 blood was practised, one of its arteries being connected with 

 an artery in a healthy dog. In a few minutes the latter 

 showed, according to the authors, tetanic symptoms. The 

 interpretation to be put on this experiment would appear to 

 be that what is called the tetanus toxine is not the real 

 poisonous agent, but that when introduced into an animal's 

 body it gives rise to chemical changes which result in the 

 true toxine being formed. This looks like a fermentative 

 action. Further, from the muscles of a tetanic dog Cour- 

 mont and Doyon prepared an extract which had the effect of 

 producing immediate tetanic spasms in a healthy animal, 

 and which, unlike the tetanus toxine, was not destroyed by 

 boiling. Careful control experiments showed that this 

 body did not exist in the muscles of normal dogs, and that 

 it was not the result of the tetanic spasms occurring in the 

 muscle of the tetanic dog. They further found that tetanus 

 toxine had no effect on a hibernating frog, but that if the 

 animal had its temperature raised to from 30 to 34 C, 

 tetanic symptoms appeared after an incubation period. 

 The interpretation they put on this experiment is that 

 at the lower temperature the toxine cannot act, while at 

 the higher it can, and this, again, is what we should expect 

 if it were a ferment. There is thus ground for suspecting 

 that the tetanus toxine (i.e., the filtrate of a tetanus culture) 

 contains a ferment which in the animal tissues produces 

 other toxic bodies. 



With regard to its physiological action, it has been shown 

 that the toxine has no effect on the sensory or motor endings 

 of the nerves, but acts solely as an exciter of the reflex 

 excitability of the motor cells in the spinal cord. The 

 motor cells in the pons and medulla are also affected, and to 

 a much greater degree than those in the cerebral cortex. 



Whatever the nature of the toxine is, it is undoubtedly 

 one of the most powerful poisons known. Even with 

 his probably impure toxalbumin Brieger found that the 

 fatal dose for a mouse was .0005 of a milligram. If 



