Research
Print page Print page
Switch language
Rigshospitalet - a part of Copenhagen University Hospital
Published

Fenfluramine Reduces [11C]Cimbi-36 Binding to the 5-HT2A Receptor in the Nonhuman Primate Brain

Research output: Contribution to journalJournal articleResearchpeer-review

DOI

  1. Neuroticism Associates with Cerebral in Vivo Serotonin Transporter Binding Differently in Males and Females

    Research output: Contribution to journalJournal articleResearchpeer-review

  2. Altered Expression Pattern of Clock Genes in a Rat Model of Depression

    Research output: Contribution to journalJournal articleResearchpeer-review

  1. A Single Dose of Psilocybin Increases Synaptic Density and Decreases 5-HT2A Receptor Density in the Pig Brain

    Research output: Contribution to journalJournal articleResearchpeer-review

  2. Effects of a single dose of psilocybin on behaviour, brain 5-HT2A receptor occupancy and gene expression in the pig

    Research output: Contribution to journalJournal articleResearchpeer-review

  3. Plasma psilocin critically determines behavioral and neurobiological effects of psilocybin

    Research output: Contribution to journalJournal articleResearchpeer-review

  4. Imaging of the Serotonin System: Radiotracers and Applications in Memory Disorders

    Research output: Chapter in Book/Report/Conference proceedingBook chapterEducation

View graph of relations

Background: [11C]Cimbi-36 is a serotonin 2A receptor agonist positron emission tomography radioligand that has recently been examined in humans. The binding of agonist radioligand is expected to be more sensitive to endogenous neurotransmitter concentrations than antagonist radioligands. In the current study, we compared the effect of serotonin releaser fenfluramine on the binding of [11C]Cimbi-36, [11C]MDL 100907 (a serotonin 2A receptor antagonist radioligand), and [11C]AZ10419369 (a serotonin 1B receptor partial agonist radioligand with established serotonin sensitivity) in the monkey brain.

Methods: Eighteen positron emission tomography measurements, 6 for each radioligand, were performed in 3 rhesus monkeys before or after administration of 5.0 mg/kg fenfluramine. Binding potential values were determined with the simplified reference tissue model using cerebellum as the reference region.

Results: Fenfluramine significantly decreased [11C]Cimbi-36 (26-62%) and [11C]AZ10419369 (35-58%) binding potential values in most regions (P < 0.05). Fenfluramine-induced decreases in [11C]MDL 100907 binding potential were 8% to 30% and statistically significant in 3 regions. Decreases in [11C]Cimbi-36 binding potential were larger than for [11C]AZ10419369 in neocortical and limbic regions (~35%) but smaller in striatum and thalamus (~40%). Decreases in [11C]Cimbi-36 binding potential were 0.9 to 2.8 times larger than for [11C]MDL 100907, and the fraction of serotonin 2A receptor in the high-affinity state was estimated as 54% in the neocortex.

Conclusions: The serotonin sensitivity of serotonin 2A receptor agonist radioligand [11C]Cimbi-36 was higher than for antagonist radioligand [11C]MDL 100907. The serotonin sensitivity of [11C]Cimbi-36 was similar to [11C]AZ10419369, which is one of the most sensitive radioligands. [11C]Cimbi-36 is a promising radioligand to examine serotonin release in the primate brain.

Original languageEnglish
JournalInternational Journal of Neuropsychopharmacology
Volume20
Issue number9
Pages (from-to)683-691
Number of pages9
ISSN1461-1457
DOIs
Publication statusPublished - 1 Sep 2017

    Research areas

  • Journal Article

ID: 51787849