RESEARCH HIGHLIGHT: SEROTONIN 2B RECEPTORS IN MESOACCUMBENS DOPAMINE PATHWAY REGULATE COCAINE RESPONSES
ENP team leader Luc Maroteaux and coll determine to unravel links between serotonin and dopamine systems in development and pathophysiological situations. Cocaïne, a powerfully addictive stimulant drug because of the changes it creates in the brain after repeated use, is known to increase levels of the brain dopamine. The authors now investigated the contribution of the serotonin 5-HT2B receptor to cocaine-dependent behavioral responses in male mice permanently lacking 5-HT2B receptors, totally or restricted to dopamine neurons. Mice exhibit a heightened cocaine-induced locomotor response reflecting therefore a higher response to the drug. Moreover, using pharmacological and electrophysiological approaches, the authors show that in animals lacking this serotonin receptor, the dopamine secretion is lower in the Nucleus accumbens (reward) by contrast to the rest of the brain. The authors highlight that these mice recapitulate a situation that has been reported in human beings that are cocaine-addicted.