A neuropeptide (i.e., peptide produced by cells of the nervous system) which is involved in activation of the immune system, pain sensation, and (when in excess) some psychiatric disorders. In the case of chronic, intractable pain (hypersensitivity), approximately one percent of the nerve cells in the human spine process substance P (thereby “transmitting” its pain message via signal transduction). In 1997, Patrick Mantyh showed that killing those (one percent) cells relieved chronic pain hypersensitivity without impairing sense of touch or normal (beneficial) pain sensation, in humans.
A peptide found in nerves that transmits pain signals.
An 11-amino acid peptide that has important functions in the body’s response to pain, noxious stimuli, depression, and anxiety. This substance may also be important in eliciting local tissue reactions resembling inflammation.