Ethanol and Mesolimbic Serotonin/Dopamine Interactions Via 5-HT1B Receptors

摘要

The experiments were carried out in 5-HT1B receptor knock-out (KO) mice and wild-type (WT) mice. One-probe microdialysis was performed. In the first set of experiments, saline or RU 24969 (0.5 and 1 mg/kg), a 5-HT1B/1A receptor agonist, was injected ip to the KO or WT mice. The results showed that administration of RU 24969 at the dose of 1 mg/kg significantly increased dopamine (DA) concentrations in the nucleus accumbens (NACC) of the WT mice but not the KO mice. In the second set of experiments, saline or ethanol (1 and 2 g/kg) was injected ip to the KO or WT mice. The results showed that administration of ethanol at the dose of 2 g/kg produced more pronounced increases in the NACO DA in the WT mice than in the KO mice. In the third set of experiments, RU 24969 (0.5 mg/kg) was injected ip to KO or WT mice. Twenty min later, each mouse received ethanol injections at the dose of I or 2 g/kg. The results showed that pretreatment with RU 24969 enhanced the effects of ethanol on NACO DA in the WT mice but not in the KO mice. These results obtained from transgenic animals provide additional support to the hypothesis that 5-HT1B receptors are partially involved in ethanol-induced increases in mesolimbic DA transmission.