ELECTROPHYSIOLOGICAL RESPONSES TO SUGARS 181 



2. Individual fibres, (i) Monosaccharides. Upon stimulation with 

 0.5 M solutions of the monosaccharides we found fibres which were acti- 

 vated by all of the sugars, but also fibres which only responded to the most 



Water 



Fig. 3. Records obtained from small strand of chorda tympani containing only 

 one functional fibre. Time in seconds. 



D-fructose 



Ml 



L- sorbose D-rnanr 



D-gaUi Joat- 



Water 



D-2luco»e NaCl O.S M 



Mm 



Fig. 4. Functional single fibre from the chorda tympani responding to D-fructose 

 only among the 0.5 m solutions of monosaccharides. Time in seconds. 



potent one, D-fructose. An example of the first type is shown in Fig. 3. 

 As usually, D-fructose produced a much more massive response in terms of 

 spikes per unit time than the other sugars. L-sorbose and D-mannose 



