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bioRxiv · 10.1101/2021.07.22.453428

Fructose appetition in "taste-blind" P2X2/P2X3 double knockout mice

Sclafani, A.·Ackroff, K.
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Abstract

Inbred mouse strains differ in their postoral appetite stimulating response (appetition) to glucose and fructose. For example, C57BL/6J (B6) and FVB strains learn strong preferences for a flavor (CS+, e.g., cherry) paired with intragastric (IG) glucose infusions, but only FVB mice learned to prefer a CS+ paired with IG fructose infusions. Consistent with these findings, "tasteless" B6 knockout (KO) mice missing the taste signaling protein TRPM5 learn strong preferences for a CS+ added to glucose solution as well as for unflavored glucose but weak or no preferences for a fructose-paired CS+ or unflavored fructose. The present experiment reports that "tasteless" P2X2/P2X3 double-knockout (P2X2/3 DKO) mice, unlike TRPM5 KO mice, learned strong preferences for a CS+ mixed with fructose as well as for unflavored fructose. Whether differences in genetic backgrounds or other factors account for the fructose appetition displayed by P2X2/3 DKO mice but not TRPM5 KO mice remains to be determined.

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Sclafani, A., Ackroff, K.. 2021-07-22. Fructose appetition in "taste-blind" P2X2/P2X3 double knockout mice. https://doi.org/10.1101/2021.07.22.453428

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