title: Phosphorus Taste Involves T1R2 and T1R3.
abstract: Rodents consume solutions of phosphates and pyrophosphates in preference to water. Recently, we found that the preference for trisodium pyrophosphate (Na3HP2O7) was greater in T1R3 knockout (KO) mice than wild-type (WT) controls, suggesting that T1R3 is a pyrophosphate detector. We now show that this heightened Na3HP2O7 preference of T1R3 KO mice extends to disodium phosphate (Na2HPO4), disodium and tetrasodium pyrophosphate (Na2H2PO4 and Na4H2PO4), a tripolyphosphate (Na5P3O10), a non-sodium phosphate [(NH4)2HPO4], and a non-sodium pyrophosphate (K4P2O7) but not to non-P salts with large anions (sodium gluconate, acetate, or propionate). Licking rates for Na3HP2O7 are higher in T1R2 KO mice than WT controls; Na3HP2O7 preference scores are increased even more in T1R2 KO mice and T1R2+T1R3 double KO mice than in T1R3 KO mice; preference scores for Na3HP2O7 are normal in T1R1 KO mice. These results implicate each subunit of the T1R2+T1R3 dimer in the behavioral response to P-containing taste compounds.
authors.affiliation: Monell Chemical Senses Center, Philadelphia, PA, USA.
authors.forename: Michael G
authors.initials: MG
authors.lastname: Tordoff
mesh_terms: D000818:Animals; D011756:Diphosphates / Q000008:administration & dosage / Q000494:pharmacology*; D005518:Food Preferences; D051379:Mice; D008810:Mice, Inbred C57BL; D018345:Mice, Knockout; D043562:Receptors, G-Protein-Coupled / Q000378:metabolism*; D013649:Taste / Q000187:drug effects* / Q000502:physiology*
chemical_list: D011756:Diphosphates; D043562:Receptors, G-Protein-Coupled; C431926:taste receptors, type 1; C003319:sodium pyrophosphate
keywords: gustometer; mineral taste; phosphate taste; preference tests.