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Updated: Jul 4, 2026
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A Plate-Based Assay for the Measurement of Endogenous Monoamine Release in Acute Brain Slices
Published on: August 11, 2021
Central aminopeptidase and serotonin system activities: possible relationship
L Cicin-Sain1, S Simaga, A Froebe
1Department of Molecular Biology, "Rudjer Bosković" Institute, Bijenicka 54, HR-10000 Zagreb, Croatia. cicinsai@irb.hr
Neuropeptides
|June 13, 2008
Summary
Altered serotonin transporter activity in rats is linked to changes in brain aminopeptidase enzymes. High serotonin transporter activity correlated with lower brain alanyl aminopeptidase and arginyl aminopeptidase activity.
Area of Science:
- Neuroscience
- Biochemistry
- Genetics
Background:
- Serotonin (5-hydroxytryptamine, 5HT) and neuroactive peptides coexist in neurons, suggesting system interactions are vital for homeostasis.
- Aminopeptidases regulate neuropeptide levels and function, but their relationship with the serotonergic system is not fully understood.
Purpose of the Study:
- To investigate the interrelations between serotonin system functioning and aminopeptidase activities.
- To analyze the impact of constitutional alterations in serotonin transporter activity on key cytosolic exopeptidases.
Main Methods:
- Utilized a novel genetic rat model with selectively bred high-5HT and low-5HT sublines exhibiting extreme serotonin transporter activity.
- Measured the activities of alanyl aminopeptidase (alanyl-AP), arginyl aminopeptidase (arginyl-AP), and dipeptidyl peptidase III (DPP III) in brain and peripheral tissues.
Main Results:
- Rats with upregulated serotonin transporter activity (high-5HT subline) showed significantly lower brain alanyl-AP (p<0.05) and arginyl-AP (p<0.01) activity compared to controls.
- No significant differences in DPP III activity or in peripheral tissues were observed across the sublines.
- The observed alterations were specific to brain aminopeptidase activity in relation to serotonin transporter levels.
Conclusions:
- Constitutional upregulation of serotonergic activity may be associated with reduced brain cytosolic aminopeptidase activity.
- This finding suggests a potential influence on neuropeptide cleavage and homeostasis within the central nervous system.
- Highlights a novel link between the serotonergic system and aminopeptidase regulation in the brain.
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