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Updated: Jul 17, 2026
07:41
A Kinetic Fluorescence-based Ca2+ Mobilization Assay to Identify G Protein-coupled Receptor Agonists, Antagonists, and Allosteric Modulators
Published on: February 20, 2018
Peptide conversion--a potential pathway modulating G-protein signaling
1Department of Pharmaceutical Biosciences, Division of Biological Research on Drug Dependence, Uppsala University, P.O. Box 591, S-751 24 UPPSALA, Sweden. Fred.Nyberg@farmbio.uu.se
Current Drug Targets
|February 3, 2007
Summary
Neuropeptides can be broken down into bioactive fragments that modulate their original effects. These fragments, derived from opioid peptides, substance P, and angiotensin II, can mimic or counteract parent peptide actions.
Area of Science:
- Pharmacology
- Neuroscience
- Biochemistry
Background:
- Neuropeptides act via G-protein coupled receptors on cell surfaces.
- Receptor activation leads to cellular effects and subsequent peptide degradation.
- Enzymatic conversion of neuropeptides can yield bioactive fragments.
Purpose of the Study:
- To review the phenomenon of bioactive peptide fragment generation.
- To focus on fragments from opioid peptides, substance P, and angiotensin II.
- To explore how these fragments modulate parent peptide actions.
Main Methods:
- Literature review of neuropeptide systems.
- Analysis of enzymatic conversion pathways.
- Examination of fragment-receptor interactions.
Main Results:
- Bioactive fragments can mimic or counteract parent peptide effects.
- Fragments may interact with the same or distinct receptors.
- Modulatory roles identified in opioid, tachykinin, and renin-angiotensin systems.
Conclusions:
- Enzymatic conversion generates bioactive fragments that modulate neuropeptide signaling.
- These fragments play a significant role in fine-tuning cellular responses.
- Understanding fragment activity is crucial for comprehending peptide system regulation.
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