The electrical activity in the chorda tympani proper nerve of dog, hamster, pig and rabbit was recorded during stimulation of the tongue with the sweet proteins, monellin and thaumatin, and stimuli representing the four taste qualities. It was observed that these proteins, which to man taste extremely sweet and in the monkey elicit a significant neural response, caused, except for monellin in the dog, no significant change in the neural activity. On the basis of these results it is suggested that different types of 'sweet' receptor sites exist in mammals.
Bibliographical noteFunding Information:
The author is indebted to Dr H. van der Wei, Unilever Research, Vlaardingen, Netherlands who supplied the monellin and thaumatin used. This study was supported by grants from Knut och Alice Wallenbergs Stiftelse, Magnus Bergvalls Stiftelse, Helge Ax:son Johnsons Stiftelse and the Swedish Medical Research Council grant No. 2467.