Neuropeptide receptor

{{Short description|Cell surface receptors that bind specific neuropeptides}}

A neuropeptide receptor is a type of G protein-coupled receptor (GPCR) that binds neuropeptides—small, protein-like molecules used by neurons to communicate{{Cite journal |last1=Zhang |first1=Yan |last2=Wang |first2=Zhiwei |last3=Parks |first3=Gregory Scott |last4=Civelli |first4=Olivier |title=Novel Neuropeptides as Ligands of Orphan G Protein-Coupled Receptors |url=https://www.eurekaselect.com/article/20188 |journal=Current Pharmaceutical Design |date=2011 |language=en |volume=17 |issue=25 |pages=2626–2631 |doi=10.2174/138161211797416110 |pmc=5828022 |pmid=21728976}}.

Neuropeptides differ from classical neurotransmitters in several key ways:

  • active at much lower concentrations
  • bind their receptors with higher affinity
  • synthesized as large inactive precursors that undergo complex processing.{{Citation |last1=Mains |first1=Richard E. |title=The Neuropeptides |date=1999 |work=Basic Neurochemistry: Molecular, Cellular and Medical Aspects. 6th edition |url=https://www.ncbi.nlm.nih.gov/books/NBK28247/ |access-date=2025-05-03 |publisher=Lippincott-Raven |language=en |last2=Eipper |first2=Betty A.}}

In contrast, neurotransmitters are typically synthesized through simpler enzymatic pathways, Neuropeptide receptors play crucial roles in modulating neuronal excitability, synaptic transmission, pain perception, mood, appetite, circadian rhythms, and stress responses.{{Cite journal |last1=Yeo |first1=Xin Yi |last2=Cunliffe |first2=Grace |last3=Ho |first3=Roger C. |last4=Lee |first4=Su Seong |last5=Jung |first5=Sangyong |date=2022-02-01 |title=Potentials of Neuropeptides as Therapeutic Agents for Neurological Diseases |journal=Biomedicines |language=en |volume=10 |issue=2 |pages=343 |doi=10.3390/biomedicines10020343 |doi-access=free |issn=2227-9059 |pmc=8961788 |pmid=35203552}}

An example is the μ-opioid receptor, which binds to and is activated by the neuropeptide β-endorphin.

Physiological Roles

Neuropeptide receptors play a role in a variety of physiological processes:

  • Neuronal Circuit Regulation – Modulate excitatory/inhibitory balance (e.g., NPY, VIP, somatostatin). Enhance synaptic plasticity and memory (e.g., galanin, adropin).
  • Sensory Processing – Mediate pain, temperature, and auditory signals (e.g., CGRP, substance P, UCN3). Integrate multisensory information for adaptive behaviors.
  • Immune and Inflammatory Modulation – Pro-inflammatory activation (CRH, CGRP, substance P). Anti-inflammatory effects (VIP, NPY, α-MSH).
  • Metabolic and Endocrine Regulation – Regulate appetite and energy balance (e.g., ghrelin, 26RFa, GLP-1). Facilitate communication between the brain, gut, and liver.
  • Neuroprotection and Neurodegeneration – Protect neurons in stroke, epilepsy, and Alzheimer’s (e.g., NPY, dynorphin). Impact processes in diseases like Parkinson’s and Huntington’s.
  • Pain and Stress Response – Opioid receptors mediate analgesia and stress (μ, δ, κ). Non-classical receptors modulate opioid peptide functions (e.g., NMDA-R, Mas-related GPCRs).
  • Behavioral and Emotional Regulation – Influence social bonding, fear, addiction, and anxiety (e.g., oxytocin, vasopressin, CRH).

See also

References

{{Reflist|2}}