Primary afferent tachykinins are required to experience moderate to intense pain.

Cao Y.Q., Mantyh P.W., Carlson E.J., Gillespie A.-M., Epstein C.J., Basbaum A.I. (1998) Primary afferent tachykinins are required to experience moderate to intense pain. Nature, 392(6674):390-4.

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