EFFECTS OF AMILORIDE ON TASTE RESPONSES OF DROSOPHILA-MELANOGASTER ADULTS AND LARVAE

Amiloride, a diuretic that blocks epithelial sodium channels, affects taste-cell responses to salts and sweet stimuli in most vertebrates. This suggests that amiloride-sensitive sodium channels mediate taste transduction in these organisms. We have shown that amiloride, when present in the stimulus solution, affects behavioural responses of Drosophila melanogaster adults to sucrose and responses of larvae to sucrose and sodium chloride. We have also shown that the drug does not repel or attract larvae. This suggests that amiloride affects salt and sweet taste perception directly, perhaps by blocking sodium channels, rather than acting as an aversive stimulus that counteracts the effect of sucrose or an attractive stimulus that counteracts the effect of sodium chloride. © 1990.