ELECTROPHYSIOLOGICAL RESPONSES TO SUGARS 

 AND THEIR DEPRESSION BY SALT 



H. T. Andersen*, M. FuNAKOSHif and Y. Zotterman 



Department of Physiology, Kungl. Veterinarhogskolan, Stockholm 51, Sweden 



Several attempts have been made to relate sweet taste to certain mole- 

 cular configurations. Well known for instance is the classification by 

 Cohn (1914) of so-called " sapophoric " groups including, among others, 

 multiple hydroxyl groups in certain molecules and the a-amino groups in 

 the amino acids. Another systematization which has been frequently 

 referred to is that of Oertly and Myers (1919), in which these authors, under 

 apparent influence of de Witt's theory for dyestuffs, postulated that a 

 *' glucophore " and an " auxogluc " are required in a molecule in order to 

 produce sweet taste. However, because of the many and important excep- 

 tions from the postulated rules, none of the theories relating sweet taste 

 to molecular configurations is comprehensive. 



Agents which taste sweet to humans are found not only among the 

 organic compounds, but include certain inorganic salts as well. However, 

 even if we limit our discussion to only the organic substances eliciting sweet 

 taste, any classification based on structural characteristics of the stimulat- 

 ing molecules will necessarily encounter serious difficulties. Firstly, be- 

 cause the sweet-tasting organic compounds belong to a wide variety of 

 chemical groups characterized by entirely dissimilar molecular skeletons. 

 Secondly, because increasing molecular weight within a homologous series 

 may be accompanied by a change in taste from sweet to bitter ; and 

 finally, because a single substitution into a complex molecule with one 

 very simple group may have a striking effect on altering the taste of the 

 original compound (Hamor, 1961). 



It appears, therefore, that our present knowledge is insufiicient to support 

 a comprehensive classification of sweet tasting compounds based on their 

 molecular configuration, and one may question whether such a systematiza- 

 tion will ever become feasible. The complexity of the situation outhned 

 above, it seemed to us, called for an investigation on a much simplified 



* Fellow of the Norwegian Research Council for Science and the Humanities, Oslo, 

 Norway. 



t On leave from Department of Physiology, Dental School, Osaka University, Osaka, 

 Japan. 



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