CHEMICAL CONSTITUTION AND PHYSIOLOGICAL ACTION. 



163 



interesting one. It is difficult to imagine a more decided modification in the 

 action of any substance than has been produced by the addition of iodide or 

 sulphate of methyl to strychnia. The striking characteristic of strychnia- action 

 is the great and uncontrollable activity of the muscular system ; that of curare, 

 of iodide, and sulphate of methyl-strychnium, and, as we shall presently see, of 

 several other similarly modified poisons, is the flaccid and motionless condition 

 caused by the impossibility of exciting muscular action through the nervous, 

 system. So opposite are their effects that physiologists look upon curare as a 

 powerful counteragent to strychnia, while physicians have employed it with 

 success in the treatment of strychnia-poisoning and of tetanus. It is remarkable 

 that by so simple a chemical process so thorough a change should be produced in 

 physiological action. 



The experiments we have already described have also shown that this change 

 in chemical constitution has greatly reduced the poisonous activity of strychnia. 

 This effect is still more clearly exhibited in the following table : — 



No.* 



Substance 



Animal and its 



Method of 



Dose. 



Effect. 





employed. 



weight. 



exhibition. 







VII. 



Iodide of methyl- 



Rabbit, 3 lbs. 8 oz. 



Subcutaneously. 



15 grs. (contain- 



Paralysis in 50 minutes, 





strychnium. 







ing 10'5 grs. 

 of strychnia). 



continuing for more than 

 2 hours, and followed by 

 recovery. 



XIII. 



Strychnia (sus- 



Do. (same rabbit 



Subcutaneously. 



0-05 gr. 



Tetanus in 15 minutes; 





pended in dis- 



as in Expt. VII.) 







death in 30 minutes. 





tilled water). 











XVII. 



Iodide of methyl- 

 strychnium. 



Do., 3 lbs. 13 oz. 



By stomach. 



30 grs. (contain- 

 ing 21'1 grs. 

 of strychnia). 



No effect. 



XIX. 



Strychnia (as 



Do., (same rabbit 



By stomach. 



01 gr. 



Tetanus in 22 minutes ; 





hydrochlorate). 



as in Ex. XVII.) 







death in 31 minutes. 



XXIII. 



Sulphate of me- 



Do., 3 lbs. 3^ oz. 



Subcutaneously. 



- 8 gr. (contain- 



Paralysis in 29 minutes, 





thyl-strych- 







ing 0.67 gr. of 



continuingfor 53 minutes, 





nium. 







strychnia). 



and followed by recovery. 



XXXIII. 



Sulphate of me- 

 thyl-strych- 

 nium. 



Do., 3 lbs. 5£ oz. 



By stomach. 



20 grs. (contain 

 ing 16"8 grs. 

 of strychnia). 



No effect. 



We have made experiments with nitrate of methyl-strychnium and hydro- 

 chlorate of ethyl-strychnium, and have found that their action is identical with 

 that of the iodide or sulphate of methyl-strychnium. 



* The numbers in this, and in the other short tables that are appended to the description of the 

 physiological action of the derivatives of each alkaloid, have reference, in common with the numbers 

 in the text, to the arrangement in the complete table at the end of the paper. 



VOL. XXV. PART I. 



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