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Updated: Jul 1, 2026

A Method of Nodose Ganglia Injection in Sprague-Dawley Rat
Published on: November 25, 2014
Anandamide effects on 5-HT(3) receptors in vivo
Ildikó Rácz1, Andras Bilkei-Gorzo, Astrid Markert
1Institute of Molecular Psychiatry, Life & Brain Center, University of Bonn, Sigmund-Freud-Strasse 25, Bonn, Germany.
Abstract:
Studies in knockout mouse strains have shown that some cannabimimetic effects persist in animals lacking cannabinoid CB(1) and CB(2) receptors. These residual effects are thought to result, in part, from a cannabinoid-modulation of ion channels. This study investigates the role of 5-HT(3) receptors as a potential in vivo target for cannabinoids. Mice deficient in CB(1) and CB(2) receptors were treated with Delta(9)-tetrahydrocannabinol and anandamide, in the presence of the 5-HT(3) antagonist ondansetron. We show that the cannabinoid receptor-independent anandamide analgesia, but not catalepsy, is completely blocked by ondansetron. Thus, 5-HT(3) receptors seem to be involved in cannabinoid analgesia.
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