Action of Salicylates 



391 



A solution of 1 :2000 caused no effect or stimulation. When 

 the concentration was 1 :1000 and the heart was exposed to the 

 action of the salicylate for ten to fifteen minutes considerable 

 depression occurred. Slight improvement was sometimes no- 

 ticed when the sodium salicylate was discontinued, but complete 

 recovery was never observed. Stronger solutions produced still 

 greater depression; 1:500 caused cessation of heart action in 

 two minutes, but some improvement also occurred in this case 

 when perfusion with Ringer's solution was resumed. With a 

 concentration of 1 :250 depression was still more pronounced. 



Marked depression of the heart also occurred when it was 

 perfused with very weak solutions of acetylsalicylic acid (1 :4000 

 to 1:2000). It was found, however, that this was due to the 

 increased hydrogen ion concentration of the solution, for by 

 adding sodium hydroxide or sodium bicarbonate until the P H 

 was 7.4 or 7.5 (the same as that of Ringer's solution) stimula- 

 tion was produced when the heart was perfused with the acetyl 

 derivative of the same molecular concentration as that of sodium 

 salicylate. Stronger concentration (1:250), however, caused 

 cardiac depression though the hydrogen ion concentration was 

 corrected as above to correspond with that of the Ringer's solu- 

 tion. The results show, therefore, that sodium salicylate is more 

 toxic than the corresponding acetyl derivative. Similar results 

 were obtained by Dreser 1 who perfused the frog heart with 

 sodium salicylate and aspirin in defibrinated ox blood. 



Experiments were also performed with methyl and ethyl 

 salicylates. A saturated solution of the former (0.07 per cent, 

 or less) produced complete heart block within two or three 

 minutes which was promptly removed by perfusion with Ringer's 

 solution alone. 



Similar effects were produced by a saturated solution of ethyl 

 salicylate, but the arrest of heart action set in after a period of 

 five to ten minutes or longer. Recovery occurred also as after 

 perfusion with methyl salicylate. 



i H. Dreser, Archiv. fur Ges. Physiol, 1899, lxxvi, 306. 



