抄録
We examined the neural mechanism of discriminative taste preference learning, using the procedure with some modifications of flavor-postingestive consequence learning paradigm in C57BL/6 male mice. Wild mice were allowed to drink water for 10 min daily with the two-bottle method after 16 h water- and food-deprivation. When mice were alternately exposed to sucrose (Suc, 0.5 M) or saccharin (Sacch, 5 mM) instead of water during 2 weeks, the amount of 0.5 M Suc consumption markedly increased but that of 5 mM Sacch did not. Because naive mice prefer to 0.5 M Suc much more than 5 mM Sacch, we employed 0.15 M Suc, to which mice showed the same preference as 5 mM Sacch, instead of 0.5 M Suc. The amount of 0.15 M Suc tended to increase with decreasing of the Sacch-consumption only when the intragastric injection of 0.5 M Suc was done. These results suggest that mice can discriminate between subtle difference cues of Suc from Sacch, mediating the association with intragastric sensory feedback in the brain. [J Physiol Sci. 2006;56 Suppl:S97]
