Substance P and pain: an updating

Substance P, discovered originally in 1931 by von Euler and Gaddum, has taken over 40 years to be appreciated as an important naturally-occurring peptide in synaptic transmission in the mammalian central nervous system. Of its various possible roles, perhaps the most clearly substantiated by experimental evidence is its involvement in gating the transfer of pain information through the spinal cord. Here James L. Henry describes how this …