Suppressive effect of mitragynine on the 5-methoxy-N,N-dimethyltryptamine-induced head-twitch response in mice.
Pharmacology, biochemistry, and behavior January 1, 1997 K Matsumoto, M Mizowaki, H Takayama et al. 60 citations
Mitragynine, a compound from kratom leaves, suppresses head-twitch responses in mice induced by a serotonin receptor agonist, similar to a known 5-HT2A receptor antagonist. The effect was dose-dependent and not altered by depleting serotonin or dopamine systems, but was reduced by drugs that block alpha-2 adrenoceptors. This suggests mitragynine acts through stimulation of postsynaptic alpha-2 adrenoceptors, blockade of 5-HT2A receptors, or both.