Substance P and the Tachykinin Family: The Neuropeptide System Linking Nociception, Neuroinflammation, and Tissue Remodeling Research

# Substance P and the Tachykinin Family: The Neuropeptide System Linking Nociception, Neuroinflammation, and Tissue Remodeling Research

Discovered nearly a century ago as an unidentified spasmogenic factor in equine brain extracts, Substance P (SP) has matured into one of the most extensively studied neuropeptides in biomedical research (PMID: 42662276). As the founding member of the tachykinin peptide family, SP operates at the intersection of the nervous and immune systems — transmitting nociceptive signals, orchestrating neurogenic inflammation, modulating cardiovascular tone, and influencing cellular proliferation pathways that remain under active investigation.

This guide provides a comprehensive, research-use-only (

References

• •PMID: 42662276
• •PMID: 42185092
• •PMID: 42069949

RUO) overview of Substance P and its tachykinin relatives: their molecular biology, receptor pharmacology, signaling mechanisms, and the expanding frontier of laboratory applications driving modern neuropeptide science.

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Historical Context: From "Preparation P" to Precision Neuropeptide Science

The story of Substance P begins in 1931, when Ulf von Euler and John Gaddum isolated a hypotensive and spasmogenic factor from equine brain and intestinal tissue extracts. Because the active principle resided in a dry powder ("P" for Pulver, the German word for powder), they named it "Preparation P" — later shortened to Substance P ([Chang & Leeman, 1970]()).

It took four decades before Susan Leeman and Michael Chang finally determined the complete amino acid sequence: Arg-Pro-Lys-Pro-Gln-Gln-Phe-Phe-Gly-Leu-Met-NH₂ — an 11-amino-acid peptide (undecapeptide) with a characteristic C-terminal amidation essential for biological activity. This achievement opened the floodgates for tachykinin research, revealing an entire peptide family that would prove central to neuroscience, immunology, and beyond.

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The Tachykinin Peptide Family: Members and Molecular Biology

Defining the Tachykinins

Tachykinins are named for their rapid ("tachy") stimulatory action on smooth muscle ("kinin"). All mammalian tachykinins share a conserved C-terminal motif — Phe-X-Gly-Leu-Met-NH₂ — that is essential for receptor binding and biological activity ([Steinhoff et al., 2014]()). The three principal mammalian tachykinins are:

Gene Organization and Processing

The TAC1 gene (also called preprotachykinin-A, or PPT-A) encodes both Substance P and Neurokinin A through alternative mRNA splicing. Four splice variants (α, β, γ, δ) produce different combinations of tachykinin peptides, with the β and γ transcripts also yielding elongated forms — Neuropeptide K (NPK, 36 aa) and Neuropeptide γ (NPγ, 21 aa), respectively — that contain the NKA sequence within their structure (Carter & Krause, 1990).

The TAC3 gene encodes Neurokinin B independently, and its expression pattern is notably distinct — concentrated in specific hypothalamic nuclei and peripheral tissues involved in reproductive neuroendocrine signaling.

This gene-level complexity means that a single transcriptional event can produce multiple bioactive tachykinin peptides, enabling nuanced, context-dependent signaling in tissues that co-express the necessary processing enzymes.

Tissue Distribution

Substance P is widely distributed throughout the central and peripheral nervous systems:

• •Central nervous system: Substantia nigra, hypothalamus, amygdala, periaqueductal gray, nucleus tractus solitarius, dorsal raphe
• •Peripheral nervous system: Primary sensory neurons (C-fibers and Aδ fibers) of dorsal root ganglia and trigeminal ganglia
• •Non-neuronal sources: Immune cells (macrophages, dendritic cells, lymphocytes), endothelial cells, fibroblasts, and enterochromaffin cells of the gastrointestinal tract

This ubiquitous distribution underscores SP's role as a pleiotropic signaling molecule operating far beyond classical neurotransmission.

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Neurokinin Receptors: NK1, NK2, and NK3 Pharmacology

Receptor Architecture

The three neurokinin receptors — NK1R, NK2R, and NK3R — are Class A (rhodopsin-like) G protein-coupled receptors (GPCRs) encoded by the TACR1, TACR2, and TACR3 genes, respectively. Each receptor possesses the canonical seven-transmembrane domain topology characteristic of GPCRs ([Garcia-Recio & Gascón, 2015]()).

While each tachykinin has a preferred receptor, the system exhibits significant cross-reactivity at higher concentrations — SP can activate NK2R and NK3R, and NKA can engage NK1R, albeit with reduced affinity. This pharmacological overlap has important implications for experimental design and data interpretation.

NK1 Receptor (TACR1)

The NK1 receptor is the primary high-affinity receptor for Substance P (K_d ≈ 0.1–0.3 nM) and the most extensively characterized member of the family:

• •Signal transduction: Couples primarily to Gαq/11, activating phospholipase C (PLC), generating inositol trisphosphate (IP₃) and diacylglycerol (DAG), mobilizing intracellular Ca²⁺, and activating protein kinase C (PKC). Also engages Gαs (adenylyl cyclase/cAMP) and Gα12/13 (Rho/ROCK) pathways depending on cellular context (Mantyh, 2002).

• •β-Arrestin recruitment: NK1R activation leads to GRK-mediated phosphorylation, β-arrestin-2 recruitment, receptor internalization via clathrin-coated pits, and sustained endosomal signaling — a process increasingly recognized as functionally distinct from plasma membrane signaling.

• •Distribution: Brain (striatum, locus coeruleus, hypothalamus), spinal cord (laminae I and II), peripheral sensory neurons, immune cells, vascular endothelium, gastrointestinal tract, and respiratory epithelium.

NK2 Receptor (TACR2)

The NK2 receptor preferentially binds Neurokinin A and is predominantly expressed in peripheral tissues:

• •Key locations: Smooth muscle of the gastrointestinal tract, airways, urinary bladder, and uterus
• •Signaling: Gαq/11-coupled PLC activation, with additional coupling to Gαs in some tissues
• •Research relevance: NK2R antagonists are under investigation as research tools for studying visceral motility, airway hyperresponsiveness, and anxiety-related behaviors (Page, 2021)

NK3 Receptor (TACR3)

The NK3 receptor is the preferred target for Neurokinin B, with a distribution pattern centered on the central nervous system:

• •Key locations: Hypothalamus (particularly the arcuate nucleus KNDy neurons), brainstem, cortex, and dorsal root ganglia
• •Signaling: Primarily Gαq/11-coupled
• •Research relevance: The NKB/NK3R system is critical in KNDy (Kisspeptin/Neurokinin B/Dynorphin) neuron signaling, which regulates pulsatile GnRH release and reproductive neuroendocrinology — connecting this pathway to Kisspeptin-10 research

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Substance P in Nociception and Neurogenic Inflammation

The Nociceptive Circuit

Substance P's role in pain signaling was among its earliest identified functions and remains a cornerstone of nociception research. SP is synthesized in the cell bodies of small-diameter primary afferent neurons (C-fibers and Aδ-fibers) within the dorsal root ganglia and trigeminal ganglia, then transported both centrally (to the spinal dorsal horn) and peripherally (to nerve terminals in skin, viscera, and joints).

Upon noxious stimulation, SP is released from central terminals in spinal cord laminae I and II, where it acts on NK1R-expressing projection neurons to facilitate the transmission of nociceptive information to supraspinal centers. Critically, SP-mediated signaling in the dorsal horn contributes to central sensitization — the amplification of pain processing that underlies chronic pain states. Research using NK1R knockout models and selective ablation of NK1R-expressing dorsal horn neurons has demonstrated that this receptor population is essential for the full expression of hyperalgesia and allodynia in laboratory models (Mantyh, 2002).

Neurogenic Inflammation

The peripheral release of SP from sensory nerve terminals represents the classical paradigm of neurogenic inflammation — a neurally mediated inflammatory response distinct from immune cell-initiated inflammation. When SP is released from peripheral C-fiber terminals, it triggers a cascade of vascular and immune events:

1. Vasodilation: SP acting on NK1R on vascular endothelial cells stimulates nitric oxide (NO) release and prostaglandin production, producing local vasodilation

2. Plasma extravasation: NK1R activation on postcapillary venule endothelium increases vascular permeability, allowing plasma protein leakage into the interstitial space

3. Mast cell degranulation: SP directly activates mast cells (via both NK1R-dependent and Mrgprb2/MRGPRX2-dependent mechanisms), releasing histamine, serotonin, and additional pro-inflammatory mediators

4. Immune cell recruitment: SP upregulates endothelial adhesion molecules (ICAM-1, VCAM-1) and stimulates the production of chemokines and cytokines from resident tissue cells

This SP-driven neurogenic inflammation creates the classical triad of redness (erythema), swelling (edema), and heat (calor) at sites of tissue injury — and its investigation continues to inform research into conditions characterized by neuroinflammatory amplification loops (Suvas, 2017).

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Substance P and the Immune System: Neuroimmune Crosstalk

SP as an Immunomodulator

Substance P is now recognized as a bidirectional neuroimmune mediator. Immune cells are not merely passive targets of SP — many actively express TAC1 and produce SP themselves, creating autocrine and paracrine signaling loops:

• •Macrophages and monocytes: SP stimulates the production of pro-inflammatory cytokines (IL-1β, IL-6, TNF-α) via NK1R-mediated NF-κB activation. It also enhances phagocytosis and reactive oxygen species (ROS) generation.

• •T lymphocytes: SP promotes T-cell proliferation, enhances interferon-γ (IFN-γ) production, and can modulate Th1/Th2 polarization depending on the local cytokine milieu.

• •Dendritic cells: SP enhances dendritic cell maturation, antigen presentation, and migratory capacity — linking nociceptive neural activity directly to adaptive immune priming.

• •Neutrophils: SP acts as a chemoattractant and enhances neutrophil adhesion, superoxide production, and degranulation.

The SP/NK1R Axis in Neuroinflammation

Research into neuroinflammation has revealed that SP/NK1R signaling plays significant roles in blood-brain barrier (BBB) permeability. SP released from perivascular sensory nerves and central neurons can increase BBB permeability through NK1R on brain endothelial cells, potentially facilitating leukocyte infiltration into the central nervous system. This pathway has become a focus of investigation in neurodegenerative and neuroinflammatory research models (Douglas & Bhatt, 2006).

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Substance P in Cardiovascular Research

SP exerts complex cardiovascular effects that reflect its widespread distribution in cardiac sensory nerves, endothelial cells, and central autonomic nuclei:

• •Vasodilation: SP is a potent endothelium-dependent vasodilator, acting through NK1R to stimulate endothelial nitric oxide synthase (eNOS) and prostacyclin production. This effect has been demonstrated across multiple vascular beds in laboratory models.

• •Cardioprotection research: Studies in isolated heart models have shown that sensory neuropeptide depletion (including SP) impairs post-ischemic recovery, suggesting a role for SP in myocardial resistance to ischemia-reperfusion injury (Ustinova et al., 1995).

• •Cardiac remodeling: SP/NK1R signaling has been implicated in adverse myocardial remodeling in experimental models of hypertension and volume overload, where it may promote fibrosis and inflammatory cell infiltration (Mistrova et al., 2016).

• •Central cardiovascular regulation: SP-containing neurons in the nucleus tractus solitarius (NTS) participate in baroreflex processing, and microinjection of SP into the NTS produces dose-dependent decreases in blood pressure and heart rate in laboratory models.

The dual nature of SP's cardiovascular effects — potentially protective in acute ischemic settings but potentially deleterious in chronic remodeling — illustrates the complexity of neuropeptide biology and highlights why context-dependent investigation remains essential.

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Substance P in Tissue Remodeling and Wound Repair Research

Wound Healing

SP has emerged as a significant player in tissue repair processes, particularly in contexts where neural innervation influences healing outcomes:

• •Fibroblast activation: SP stimulates fibroblast proliferation, migration, and collagen synthesis through NK1R-mediated signaling, including ERK1/2 and PI3K/Akt pathway activation.

• •Angiogenesis: Controlled-release studies have demonstrated that SP promotes neovascularization by mobilizing CD29⁺ stromal-like cells and enhancing endothelial cell proliferation, migration, and tube formation (Ko et al., 2010).

• •Keratinocyte responses: SP and NKA induce nerve growth factor (NGF) production in keratinocytes, creating neurotrophic feedback loops that may sustain neural reinnervation during tissue repair (Amann et al., 2001).

• •Inflammatory cell recruitment: In wound models, SP enhances the early inflammatory phase by recruiting macrophages and increasing local cytokine concentrations, which is essential for the transition to proliferative healing phases.

Research in denervated wound models has shown that loss of SP-containing sensory innervation significantly impairs healing kinetics, establishing a direct link between neuropeptide signaling and tissue repair competence. This finding has spurred investigation into SP as a potential component of engineered tissue scaffolds and biomaterial systems.

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Substance P in Gastrointestinal Research

The gastrointestinal (GI) tract is one of the richest sources of SP in the body, where it serves as both a neurotransmitter in the enteric nervous system (ENS) and a paracrine signaling molecule:

Motility and Secretion

SP and NKA are co-released from enteric motor neurons and act on NK1R and NK2R on smooth muscle cells to promote contractile activity. This tachykinin-mediated excitatory drive is a fundamental component of peristalsis and segmental contractions throughout the GI tract (Holzer & Holzer-Petsche, 2001).

Gut-Brain Axis Signaling

Emerging research has positioned SP as a key mediator within the microbiota-gut-brain axis. The peptide modulates:

• •Intestinal barrier integrity: SP/NK1R signaling can influence tight junction protein expression and epithelial permeability
• •Enteric immune responses: SP released from enteric neurons communicates directly with gut-associated lymphoid tissue (GALT)
• •Vagal afferent signaling: SP modulates the sensitivity of vagal afferent neurons to luminal stimuli, providing a pathway for gut-to-brain information transfer

A 2025 study published in Nature Communications demonstrated that SP administration protected against intestinal injury and associated anxiety-like behavioral changes in laboratory models, with effects linked to modulation of gut microbiota composition and inositol metabolism — highlighting the far-reaching implications of enteric SP signaling for both gastrointestinal and central nervous system research.

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The SP/NK1R System in Cell Proliferation Research

NK1R in Oncology Research

An expanding body of literature has identified the SP/NK1R axis as a significant signaling system in cell proliferation and survival:

• •Mitogenic signaling: SP binding to NK1R activates MAPK/ERK, PI3K/Akt, and Src family kinase pathways that promote cell cycle progression (Garnier et al., 2019).

• •Anti-apoptotic effects: NK1R activation by SP upregulates anti-apoptotic proteins (Bcl-2, survivin) and can counteract pro-apoptotic signals through Akt-mediated phosphorylation of Bad and caspase-9.

• •Angiogenic signaling: SP stimulates the production of vascular endothelial growth factor (VEGF) and other angiogenic factors from NK1R-expressing cells.

• •Migratory and invasive behavior: SP/NK1R signaling activates matrix metalloproteinase (MMP) expression and cytoskeletal rearrangement pathways (via Rho/ROCK) that enhance cellular motility in vitro.

NK1R has been found to be overexpressed in multiple cell line models, and NK1R antagonists (discussed below) have shown the ability to inhibit proliferation and induce apoptosis in these systems — making the SP/NK1R axis an active area of mechanistic investigation.

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NK1R Antagonists as Research Tools

Peptide and Non-Peptide Antagonists

The development of NK1R antagonists has provided invaluable pharmacological tools for dissecting tachykinin biology:

Early peptide antagonists:

• •Spantide I and II: First-generation peptide-based NK1R antagonists derived from SP's structure, useful for in vitro receptor characterization but limited by metabolic instability and poor bioavailability.

Non-peptide antagonists (the breakthrough):

• •CP-96,345: The first high-affinity non-peptide NK1R antagonist, which demonstrated species-dependent binding profiles and helped establish the pharmacological distinction between rodent and primate NK1R.
• •L-733,060: A widely used research tool with high selectivity for NK1R and good CNS penetration.
• •Aprepitant (MK-869): The most well-known NK1R antagonist, originally developed and approved for chemotherapy-induced emesis research. Aprepitant has since been used as a pharmacological probe across numerous research domains including affective neuroscience, oncology, and inflammation.

Research Applications of NK1R Antagonism

NK1R antagonists have enabled mechanistic studies across diverse research areas:

• •Nociception: Elucidating SP's contribution to central sensitization and chronic pain circuitry
• •Affective neuroscience: Investigating the role of SP/NK1R in stress responses, anxiety-like behavior, and mood regulation — SP/NK1R is intimately associated with ascending 5-HT and norepinephrine projections (Rupniak, 2002)
• •Emesis circuits: Understanding the central mechanisms of nausea and vomiting through NK1R's expression in the nucleus tractus solitarius and area postrema
• •Cell proliferation: Probing the contribution of SP/NK1R signaling to mitogenic and anti-apoptotic pathways

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Connections to Other Research Peptides

Substance P operates within a rich neuropeptide network, and understanding its interactions with other signaling systems enhances experimental design:

• •CGRP (Calcitonin Gene-Related Peptide): SP and CGRP are co-localized in many primary sensory neurons and released together during neurogenic inflammation. While SP drives plasma extravasation, CGRP is the primary mediator of neurogenic vasodilation — their combined actions produce the full neurogenic inflammatory response.

• •VIP (Vasoactive Intestinal Peptide): In the enteric nervous system, SP and VIP often serve opposing functions — SP is excitatory to smooth muscle while VIP is inhibitory — creating the balanced motility patterns essential for normal GI function.

• •PACAP: Like SP, PACAP is expressed in sensory neurons and participates in neuroinflammatory cascades. Research comparing SP- and PACAP-mediated mast cell activation has revealed distinct degranulation profiles.

• •Kisspeptin-10: The NKB/NK3R component of KNDy neurons directly connects tachykinin biology to reproductive neuroendocrine research through the regulation of pulsatile GnRH secretion.

• •Semax and Selank: As neuropeptides investigated for neuroprotective and anxiolytic properties, Semax and Selank operate in neural circuits where SP/NK1R signaling provides modulatory input — particularly in stress-responsive pathways.

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Handling Substance P in the Laboratory

Physicochemical Properties

• •Molecular formula: C₆₃H₉₈N₁₈O₁₃S
• •Molecular weight: 1,347.63 Da
• •Isoelectric point: ~11.5 (highly basic due to Arg and Lys residues)
• •Solubility: Freely soluble in water and dilute acetic acid; soluble in DMSO. Stock solutions at 1 mM in sterile water or 0.1% acetic acid are standard.

Stability Considerations

SP is susceptible to enzymatic degradation by multiple peptidases:

• •Neutral endopeptidase (NEP/CD10, neprilysin): Cleaves SP at the Gln⁶-Phe⁷ and Phe⁷-Phe⁸ bonds
• •Angiotensin-converting enzyme (ACE): Removes the C-terminal dipeptide Leu-Met-NH₂
• •SP-degrading enzyme (SPE): A membrane metalloprotease active in the CNS

For in vitro work, include protease inhibitors (e.g., phosphoramidon for NEP, captopril for ACE) when prolonged SP exposure is required. Aliquot and store lyophilized peptide at −20°C to −80°C; reconstituted solutions are best used fresh or stored in single-use aliquots at −80°C to prevent freeze-thaw degradation. For more on peptide storage, see our guide on Peptide Storage Best Practices.

Bioassay and Detection Methods

Common approaches for SP quantification and functional assessment include:

• •Radioimmunoassay (RIA) and ELISA: For measuring SP concentrations in tissue extracts, plasma, and cell culture supernatants
• •HPLC with mass spectrometry: For precise quantification and metabolite identification (see our HPLC and Mass Spectrometry guide). Read researcher reviews to identify vendors whose Substance P consistently passes HPLC purity benchmarks
• •Calcium mobilization assays: Monitoring intracellular Ca²⁺ flux as a real-time readout of NK1R activation
• •β-Arrestin recruitment assays: For studying biased agonism and receptor desensitization kinetics
• •Immunohistochemistry: For mapping SP distribution in tissue sections using validated anti-SP antibodies

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Current Research Frontiers

Biased Agonism and Endosomal Signaling

One of the most exciting developments in tachykinin research is the recognition that NK1R exhibits location-biased signaling. Recent studies have demonstrated that SP-NK1R complexes continue to signal from endosomes after internalization, generating sustained cAMP and ERK activation that is qualitatively and quantitatively distinct from plasma membrane signaling. This endosomal signaling pool may be particularly relevant to sustained nociceptive transmission and has opened new avenues for designing endosome-targeted antagonists that could block pain signaling without affecting other NK1R functions.

Truncated Tachykinins and Signaling Bias

A 2025 study by Petersen et al. in the Journal of Biological Chemistry demonstrated that truncated tachykinin fragments exhibit biased activity at NK1R and NK2R, activating some signaling pathways while failing to engage others. This work has implications for understanding endogenous SP metabolites as potential biased ligands and for designing pathway-selective research tools.

Neuroimmune Interfaces

The bidirectional communication between SP-expressing neurons and immune cells continues to yield new insights. Research is increasingly focused on:

• •Neuro-immune synapses: Direct physical contacts between SP-containing nerve terminals and tissue-resident immune cells
• •Nociceptor-driven immunity: The concept that pain-sensing neurons actively shape immune responses through SP and other neuropeptide release
• •Neuronal control of barrier immunity: SP's role in regulating mucosal immune responses at intestinal, respiratory, and cutaneous barriers

Engineered Tachykinin Analogs

Researchers are developing modified SP analogs with enhanced stability, receptor selectivity, or biased signaling profiles for use as precision research tools. Approaches include:

• •D-amino acid substitution: Creating protease-resistant analogs for prolonged in vivo studies
• •Cyclization: Constraining peptide conformation to enhance receptor subtype selectivity
• •PEGylation and lipidation: Extending pharmacokinetic profiles for sustained exposure studies (see our guide on Peptide Bioconjugation Strategies)

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Summary

Substance P and the tachykinin peptide family represent one of the most extensively characterized neuropeptide systems in biomedical research. From its discovery as an anonymous spasmogenic extract in 1931 to its current status as a pleiotropic neuroimmune mediator, SP has continuously revealed new layers of biological complexity. The three-receptor system (NK1R, NK2R, NK3R), the multi-gene tachykinin family (TAC1, TAC3), and the diverse tissue distribution of these components create a signaling network that touches virtually every organ system.

For laboratory researchers, SP and the tachykinins offer a rich pharmacological toolkit: well-characterized receptor agonists and antagonists, validated bioassay platforms, and an ever-expanding understanding of signaling mechanisms — from biased agonism to endosomal signaling to neuro-immune interfaces. As research tools become more sophisticated and our understanding of context-dependent tachykinin signaling deepens, this ancient neuropeptide family continues to generate new questions and new possibilities for investigation.

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References

2. Steinhoff MS, von Mentzer B, Geppetti P, Pothoulakis C, Bunnett NW. Tachykinins and their receptors: contributions to physiological control and the mechanisms of disease. Physiol Rev. 2014;94(1):265-301. PubMed

3. Carter MS, Krause JE. Structure, expression, and some regulatory mechanisms of the rat preprotachykinin gene encoding substance P, neurokinin A, neuropeptide K, and neuropeptide gamma. J Neurosci. 1990;10(7):2203-2214. PubMed

5. Mantyh PW. Neurobiology of substance P and the NK1 receptor. J Clin Psychiatry. 2002;63 Suppl 11:6-10. PubMed

6. Page NM. Tachykinin NK2 antagonist for treatments of various disease states. Neuropeptides. 2021;90:102185. PubMed

7. Suvas S. Role of substance P neuropeptide in inflammation, wound healing, and tissue homeostasis. J Immunol. 2017;199(5):1543-1552. PubMed

8. Douglas SD, Leeman SE. Neurokinin-1 receptor: functional significance in the immune system in reference to selected infections and inflammation. Ann N Y Acad Sci. 2011;1217:83-95. PubMed

9. Ustinova EE, Bergren D, Bhatt S, Schultz HD. Neuropeptide depletion impairs postischemic recovery of the isolated rat heart: role of substance P. Cardiovasc Res. 1995;30(1):55-63. PubMed

10. Mistrova E, Kruzliak P, Chottova Dvorakova M. Role of substance P in the cardiovascular system. Neuropeptides. 2016;58:41-51. PubMed

11. Ko MC, Husbands SM, Hammer GB, et al. Angiogenesis induced by controlled release of neuropeptide substance P. Acta Biomater. 2010;6(9):3596-3604. PubMed

12. Amann R, Egger T, Gassner M, et al. The neurosensory tachykinins substance P and neurokinin A directly induce keratinocyte nerve growth factor. J Invest Dermatol. 2001;117(5):1075-1082. PubMed

13. Holzer P, Holzer-Petsche U. Tachykinins in the gut. Part I. Expression, release and motor function. Pharmacol Ther. 2001;73(3):173-217. PubMed

14. Garnier A, Ilmer M, Kappler R, Berger M. The emerging role of substance P/neurokinin-1 receptor signaling pathways in growth and development of tumor cells. J Physiol Biochem. 2019;75(4):415-421. PubMed

15. Rupniak NM. New insights into the antidepressant actions of substance P (NK1 receptor) antagonists. Can J Physiol Pharmacol. 2002;80(5):489-494. PubMed

16. Pennefather JN, Lecci A, Candenas ML, Patak E, Pinto FM, Maggi CA. Tachykinins and tachykinin receptors: a growing family. Life Sci. 2004;74(12):1445-1463. PubMed

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Research Tools

Researchers sourcing this peptide for laboratory investigation can use the peptide price comparison tool to identify research-grade material from verified suppliers. For peer experiences with specific vendors, see researcher-submitted supplier reviews. For reconstitution planning, the peptide calculator provides molar mass, concentration, and dilution calculations.

This article is intended for educational and research purposes only. The compounds discussed are research chemicals intended for laboratory investigation. Always follow institutional guidelines and applicable regulations when conducting research.

Last updated: March 2026

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Further Reading:

• •CGRP (Calcitonin Gene-Related Peptide): The Vasodilatory Neuropeptide Bridging Pain, Cardiovascular, and Tissue Repair Research
• •Galanin: The Pleiotropic Neuropeptide Bridging Neuroscience, Metabolic, Pain, and Oncology Research
• •Vasoactive Intestinal Peptide (VIP): The Pleiotropic Neuropeptide in Neuroimmune and Circadian Research
• •Vasopressin (Arginine Vasopressin / AVP): The Antidiuretic Neuropeptide Governing Water Balance, Stress, and Social Behavior Research
• •Reconstitution Calculator
• •Peptide Stack Builder