Strain differences in amiloride inhibition of NaCl responses in mice, Mus musculus

Abstract

The effects of lingual treatment with amiloride, an inhibitor of salt taste responses in several mammalian species, on NaCl responses of the chorda tympani nerve were compared between four inbred strains of mouse (BALB/cCrSlc, DBA/2CrSlc, C57BL/6CrSlc and C3H/HeSlc). In C57BL and C3H mice amiloride significantly suppressed responses of the chorda tympani nerve to NaCl at a concentration 0.1 M or more whereas in BALB and DBA mice the drug did not significantly affect the responses to NaCl at any concentration, suggesting a lack of the amiloride-sensitive receptor component for NaCl in the latter two strains. A two-bottle preference test demonstrated that all strains of mouse usually showed no preference for NaCl at any concentration and avoided NaCl at 0.3 M or more, although some differences were observed in that C57BL and C3H mice showed aversive responses to 0.1 and 0.15 M NaCl, whereas BALB and DBA mice were indifferent to these solutions. The results suggest that there exist prominent differences between mouse strains in the amiloride-sensitive component of their salt receptor systems. However, in mice the taste information derived from the amiloride-sensitive receptor component probably has no remarkable effect on behavioral responses to NaCl except for a possible contribution to decreasing aversion thresholds for NaCl by increasing overall taste information about NaCl.

Consumption of electrolytes and quinine by mouse strains with different blood pressures1

“…These results provide new characteristics of salt acceptance in the mouse and together with the previous data (2)(3)(4)19,23,32), they show that the range of responses to sodium, potassium and calcium salts is similar in mouse and rat strains (1,8,21,28,29).…”

“…The BPN and BPL mouse strains had strong preferences for 37.5-150 mM NaCl compared with the BPH strain tested here and mouse strains tested in other studies, which either only moderately preferred these NaCl concentrations, or did not prefer them at all (2)(3)(4)19,23). The BPH, BPN and BPL mice originate from a population derived from an eight-way cross of eight inbred mouse strains (25).…”

“…The pattern of strain differences varied according to the taste compound tested. This suggests that the strain differences described here reflect specific taste and/or postingestive properties of the examined solutions, rather than generalized responses to taste novelty, or nonspecific differences in taste responsiveness.The BPN and BPL mouse strains had strong preferences for 37.5-150 mM NaCl compared with the BPH strain tested here and mouse strains tested in other studies, which either only moderately preferred these NaCl concentrations, or did not prefer them at all (2)(3)(4)19,23). The BPH, BPN and BPL mice originate from a population derived from an eight-way cross of eight inbred mouse strains (25).…”

Modulation of Taste Responsiveness by Angiotensin II

“…The diuretic agent amiloride, a sodium channel blocker, selectively suppresses taste responses to NaCl, but not to sweet, sour, and bitter substances in many mammals (Schiffman et al, 1983, Heck et al, 1984, Jakinovich 1985, Simon et al, 1986, Herness 1987, Ninomiya et al, 1989, Hellekant and Ninomiya, 1991. Subsequent studies using amiloride in rodents suggested that two distinct components underlie cellular sensitivity to NaCl: one that is amiloride-sensitive and another that is amilorideinsensitive.…”

“…Therefore, ENaC was predicted to be a potential amiloride-sensitive salt taste receptor based on the results of multiple studies (Schiffman et al, 1983, Heck et al, 1984, Jakinovich 1985, Simon et al, 1986, Herness 1987, Ninomiya et al, 1989, Hellekant and Ninomiya, 1991. It was demonstrated several years ago that the ENaC α-subunit (αENaC) plays an essential role as a receptor for amiloride-sensitive sodium taste in mice, since taste-cell-specific αENaC knockout (KO) mice exhibited a complete loss of amiloride-sensitive sodium taste response without any effect on responses to other salts or sweet, umami, bitter and sour substances (Chandrashekar et al, 2010).…”