1903.] 



The Physiological Action of Betaine. 



347 



pt. No. 6. Cat, 2*6 kilos. Respiration and blood-pressure record. Three successive injections 

 of betaine hydrochloride, 10 per cent, solution, neutralised by NaOH (extracted from raw 

 beet-sugar by Dr. Plimmer). (See continuation on following page.) 



It appears from these experiments that betaine (as hydrochloride 

 injected per venam) acts directly upon the heart; that commercial 

 betame (Merck) is more powerful than betaine extracted from beet- 

 sugar (Plimmer). 



In all instances the mode of death has been by cardiac syncope from 

 which no recovery could be obtained by artificial respiration. With 

 sublethal doses the characteristic effect was a temporary fall of blood 

 pressure, with a slight augmentation of the respiratory movements. 



The difference of action between commercial betame and betame 

 from sugar gave rise to several reflections. Unlike muscarine, of 

 which at least two chemical varieties are known, having quite different 

 physiological actions, betaine is a single well-defined chemical substance 

 that, if pure, should be of constant composition and action. Analysis 

 of a commercial sample of betaine (Schuchardt) by Dr. Plimmer 

 revealed the rather surprising fact that the sample in question 

 contained a large proportion of potassium chloride, quite enough to 

 exercise a direct depressant effect upon the heart's action. The 

 difference between commercial and laboratory betaine is thus very 

 probably due to impurity in the former. 



