TASTE RECEPTOR STIMULATION AND FEEDING-BEHAVIOR IN THE PUFFER, FUGU-PARDALIS .1. EFFECT OF SINGLE CHEMICALS

In electrophysiological experimentation, various chemicals are effective in stimulating the lip chemoreceptors of the puffer, Fugu pardalis (Hidaka et al., 1975; Kiyohara et al., 1975a). Their effects as feeding stimulants on this fish were studied by offering the lip stimulants in starch pellets. The starch pellet by itself was not taken by the fish but it was accepted when stimulants such as clam extracts were addded to it. Sucrose, ineffective as a lip chemoreceptor stimulant, had no effect on feeding behaviour. NaCl, to which the lip chemoreceptors show a low sensitivity, did not affect the feeding response when added at 2 M to clam extracts. HCl and quinine inhibited the response of the fish to the clam extracts. Alanine and other amino acids, which were effective on the lip chemoreceptors, were accepted. AMP, IMP, UMP and ADP were not accepted in spite of their marked stimulatory effectiveness on the lip chemoreceptors. Sodium salts of fumaric, malic and succinic acids were not accepted. © 1978 Information Retrieval Ltd, 1 Falconberg Court, London WIV 5FG, England.