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Multi-Faceted Mass Spectrometric Investigation of Neuropeptides in Callinectes sapidus
Published on: May 31, 2022
Neuropeptides and their peptidases: Functional considerations.
G M Littlewood1, L L Iversen, A J Turner
1MRC Membrane Peptidase Research Group, Department of Biochemistry, University of Leeds, Leeds LS2 9JT, U.K.
Neurochemistry International
|May 27, 2010
Summary
Endopeptidase-24.11 plays a key role in inactivating neuropeptides like substance P in the brain. This finding helps understand neuropeptide regulation and potential therapeutic targets.
Area of Science:
- Neuroscience
- Biochemistry
- Pharmacology
Background:
- Brain membrane peptidases are crucial for neuropeptide metabolism.
- Endopeptidase-24.11 and angiotensin converting enzyme are key enzymes involved in neuropeptide degradation.
Purpose of the Study:
- To review the properties of brain membrane peptidases, focusing on endopeptidase-24.11 and angiotensin converting enzyme.
- To define substrate specificities and assess the contribution of these enzymes to tachykinin degradation.
- To investigate the physiological roles of peptidases using selective inhibitors and brain slice preparations.
Main Methods:
- Review of peptidase properties and substrate specificities.
- In vitro studies on tachykinin degradation.
- Application of peptidase inhibitors to study neuropeptide release from rat substantia nigra brain slices.
Main Results:
- Endopeptidase-24.11 inhibition significantly increased substance P recovery from rat brain slices.
- Angiotensin converting enzyme inhibition had no significant effect on substance P recovery.
- Endopeptidase-24.11's specificity and distribution align with a role in inactivating tachykinins and enkephalins.
Conclusions:
- Endopeptidase-24.11 is implicated in the physiological inactivation of tachykinins and enkephalins in the brain.
- Luteinizing hormone-releasing hormone (LHRH) and atrial natriuretic peptide may be peripheral substrates for endopeptidase-24.11.
- The endogenous neuropeptide substrates for striatal angiotensin converting enzyme require further investigation.
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