Sour taste is mediated by
Salt ⇒ mediated by Na+ selective channel (ENaC)
Sour ⇒ mediated by H+ ions permeable to ENaCs
Bitter, sweet, umami ⇒ mediated by G-protein coupled receptors
Na+ selective channel (ENac)
G - protein coupled receptors
H+ ions permeable to ENaCs
Glutamate receptors