Substance P TFA (Neurokinin P TFA) is a neuropeptide that functions as both a neurotransmitter and neuromodulator in the central nervous system, specifically targeting the neurokinin 1 receptor (NK1-receptor, NK1R).
Substance P (1-9) is a nonapeptide that reduces the inactivation of substance P in the guinea-pig ileum and urinary bladder, and is responsible for various excitatory effects on central and peripheral neurons.