Substance P (1-9) is the N-terminal nonapeptide Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-OH. Unlike native Substance P, it lacks Leu10 and the amidated Met11 residue that form part of the C-terminal tachykinin receptor pharmacophore.

SP(1-9) is therefore best used as a Substance P degradation and N-terminal fragment reagent rather than as a direct replacement for the native NK1 agonist. Its distinct terminal chemistry is particularly relevant in protease, metabolite-identification and fragment-signaling experiments.

Product Information

Loss of Leu10-Met11-NH2

SP(1-9) removes the terminal Leu-Met-NH₂ portion of native Substance P. The resulting fragment no longer contains the complete C-terminal tachykinin pharmacophore.

This structural difference should be considered when designing receptor experiments because the fragment is chemically and pharmacologically distinct from full-length Substance P.

Research Applications

Substance P (1-9) can support peptide degradation studies, protease assays, LC-MS/MS metabolite identification and investigations of N-terminal Substance P fragment biology.

Frequently Asked Questions

Is SP(1-9) amidated?

No. It terminates in Gly-OH.

Does it contain Met11?

No.

Should it be used as an NK1 agonist control?

Not as a direct substitute for full-length Substance P because the native C-terminal pharmacophore is incomplete.

Research Use Only.