Endomorphin-1 and -2 Cause Pain at High Doses Through Different Mechanisms in the Brain
High-dose endomorphin-1 and endomorphin-2 both caused anti-analgesia (pain) in the brainstem, but through different mechanisms — endomorphin-1 via direct NMDA activation, endomorphin-2 via dynorphin release — different peptides, different pronociceptive pathways.
Quick Facts
What This Study Found
High-dose endomorphin-1 anti-analgesia in ventral PAG was mediated by direct NMDA receptor activation, while endomorphin-2 worked through dynorphin A release → kappa/NMDA pathways — two endogenous mu-agonists producing pain through distinct mechanisms.
Key Numbers
How They Did This
animal-study study on opioid-peptides, pain.
Why This Research Matters
Relevant for opioid-peptides, pain.
The Bigger Picture
Advances peptide/biomarker research.
What This Study Doesn't Tell Us
See abstract.
Questions This Raises
- ?Further research needed.
- ?Clinical translation to evaluate.
Trust & Context
- Key Stat:
- Key finding High-dose endomorphin-1 anti-analgesia in ventral PAG was mediated by direct NMDA receptor activation, while endomorphin-2 worked through dynorphin A
- Evidence Grade:
- preliminary evidence.
- Study Age:
- Published in 2005.
- Original Title:
- Differential mechanisms of antianalgesia induced by endomorphin-1 and endomorphin-2 in the ventral periaqueductal gray of the rat.
- Published In:
- The Journal of pharmacology and experimental therapeutics, 312(3), 1257-65 (2005)
- Authors:
- Terashvili, Maia(2), Wu, Hsiang-En(5), Leitermann, Randy J(4), Sun, Han-Sen, Clithero, Andrew D, Tseng, Leon F
- Database ID:
- RPEP-01090
Evidence Hierarchy
Tests effects in animals (usually mice or rats), not humans.
What do these levels mean? →Frequently Asked Questions
What was studied?
Endomorphin-1 and -2 Cause Pain at High Doses Through Different Mechanisms in the Brain
What was found?
High-dose endomorphin-1 and endomorphin-2 both caused anti-analgesia (pain) in the brainstem, but through different mechanisms — endomorphin-1 via direct NMDA activation, endomorphin-2 via dynorphin release — different peptides, different pronociceptive pathways.
Read More on RethinkPeptides
Cite This Study
https://rethinkpeptides.com/research/RPEP-01090APA
Terashvili, Maia; Wu, Hsiang-En; Leitermann, Randy J; Sun, Han-Sen; Clithero, Andrew D; Tseng, Leon F. (2005). Differential mechanisms of antianalgesia induced by endomorphin-1 and endomorphin-2 in the ventral periaqueductal gray of the rat.. The Journal of pharmacology and experimental therapeutics, 312(3), 1257-65.
MLA
Terashvili, Maia, et al. "Differential mechanisms of antianalgesia induced by endomorphin-1 and endomorphin-2 in the ventral periaqueductal gray of the rat.." The Journal of pharmacology and experimental therapeutics, 2005.
RethinkPeptides
RethinkPeptides Research Database. "Differential mechanisms of antianalgesia induced by endomorp..." RPEP-01090. Retrieved from https://rethinkpeptides.com/research/terashvili-2005-differential-mechanisms-of-antianalgesia
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkPeptides research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.