Amiloride does not alter NaCl avoidance in Fischer-344 rats

Fischer-344 (F-344) rats differ from other common rat strains in that theyfail to show any preference for NaCl at any concentration in two- bottlepreference tests. Because 100 microM amiloride partially blocks theNaCl-evoked chorda tympani (CT) response in electrophysiological studies,we tested NaCl preference (0.068-0.273 M) in F-344 rats with and without100 microM amiloride solution as the solvent. A third group was tested withunadulterated NaCl solutions following CT transection. Amiloride had nosignificant effect on the NaCl preference-aversion function, whereas CTtransection significantly reduced NaCl avoidance. These results suggestthat the amiloride-sensitive component of the NaCl response is notnecessary for F-344 rats to display avoidance of NaCl, but the entire CTinput is.