[Tyr6,D-Phe7,D-His9]-Substance P (6-11), commonly known as Sendide, is a six-residue modified Substance P fragment developed as a peptide antagonist of the neurokinin-1 receptor.

The sequence incorporates Tyr6, D-Phe7 and D-His9 and retains the C-terminal Leu-Met-NH₂ region. Classical binding and functional studies characterized Sendide as a selective and potent NK1 receptor antagonist.

Product Information

Sendide Converts a Substance P Fragment into an NK1 Antagonist

The C-terminal region of Substance P contains important receptor-recognition determinants. Sendide modifies this region using D-amino acids that alter stereochemistry and conformational preference.

The resulting peptide behaves differently from agonist Substance P fragments and can competitively interfere with NK1-mediated responses.

NK1 Antagonist Pharmacology

Sendide competitively displaced labeled Substance P from mouse spinal cord membranes and antagonized Substance P-induced behavioral responses after intrathecal administration.

It also inhibited responses to several other NK1-active tachykinin agonists, whereas substantially larger doses were required to interfere with Neurokinin A or Neurokinin B responses.

We therefore recommend describing Sendide specifically as an NK1 antagonist rather than using a generic “Substance P analog” label.

Research Applications

Sendide can support NK1 receptor antagonist studies, Substance P signaling experiments, pain and hyperalgesia research, spinal pharmacology and tachykinin receptor differentiation.

Frequently Asked Questions

What is Sendide?

Sendide is another name for [Tyr6,D-Phe7,D-His9]-Substance P (6-11).

Is Sendide an NK1 agonist?

No. It is characterized as a selective peptide NK1 receptor antagonist.

Why are D-amino acids included?

D-Phe7 and D-His9 alter peptide stereochemistry and receptor interactions relative to the native Substance P fragment.

Does Sendide contain methionine?

Yes. It terminates in Leu-Met-NH₂, so methionine oxidation remains relevant.

Research Use Only.