The spinal-cord counterpart to endomorphin-1, differing by a single aromatic residue.
Also known as: EM-2
Part of the Neuropeptides & signaling cluster
Overview
Endomorphin-2 (Tyr-Pro-Phe-Phe-NH2) is an endogenous opioid tetrapeptide and a highly selective mu-opioid receptor agonist. It differs from endomorphin-1 by one residue and is more prevalent in the spinal cord. It is used as a research tool, and this page is educational only.
Source & context
Biological / chemical source: Mammalian central nervous system (endogenous), enriched in spinal cord
Primary research or clinical context: Endogenous neuropeptide and research tool in opioid pharmacology; not a Health Canada-authorized product
One-residue difference
Endomorphin-2 shares the Tyr-Pro-Phe-Phe-NH2 scaffold with endomorphin-1 but replaces the third-position tryptophan with phenylalanine. Both are amidated tetrapeptides with high mu-opioid selectivity, but endomorphin-2 is comparatively enriched in the spinal cord, making the pair a useful lesson in how small sequence changes shape distribution and pharmacology.
Research role and limits
Endomorphin-2 is used in laboratory studies of opioid receptor signalling and spinal analgesia in animal models. Like endomorphin-1 it is rapidly degraded and poorly brain-penetrant, so it remains a research probe rather than a medicine. This page is educational and makes no claim about pain or any medical use.
FAQ about Endomorphin-2
What is Endomorphin-2?+
Endomorphin-2 (Tyr-Pro-Phe-Phe-NH2) is an endogenous opioid tetrapeptide and a highly selective mu-opioid receptor agonist. It differs from endomorphin-1 by one residue and is more prevalent in the spinal cord. It is used as a research tool, and this page is educational only.
Is Endomorphin-2 an approved medicine?+
Endomorphin-2 is discussed here as a research / educational topic. Endogenous neuropeptide and research tool in opioid pharmacology; not a Health Canada-authorized product. This is not medical advice.
What is the typical length of Endomorphin-2?+
Endomorphin-2 is commonly described as approximately 4 amino acids (Endogenous opioid tetrapeptide).