Grant K A, Colombo G
Department of Physiology and Pharmacology, Bowman Gray School of Medicine, Wake Forest University, Winston-Salem, North Carolina 27157-1083.
Psychopharmacology (Berl). 1993;113(1):26-30. doi: 10.1007/BF02244329.
The role of the ethanol training dose on the ability of the selective 5-HT1 agonist TFMPP (m-trifluoromethylphenylpiperazine) to produce ethanol-like discriminative stimulus effects was evaluated in three groups of rats trained to discriminate 1.0 g/kg (n = 5), 1.5 g/kg (n = 6) or 2.0 g/kg (n = 7) ethanol (IG) from water using a two-lever procedure with food reinforcement available under a fixed ratio 20 (FR 20) schedule. Ethanol generalization gradients were comparable in the three groups, indicating few potency differences in the ethanol stimulus across training dose. However, the ability of TFMPP (0.1-1.7 mg/kg; IP) to substitute for ethanol was dependent on the training dose. TFMPP resulted in partial substitution in the 1.0 g/kg group, complete substitution for 1.5 g/kg group and no substitution in the 2.0 g/kg ethanol training group. The results indicate a serotonergic component to the discriminative stimulus effects of an intermediate dose of ethanol that is not prominent as the dose of ethanol is raised. These data add further support for the hypothesis that ethanol produces a mixed discriminative cue, the components of which are not uniformly amplified when the dose of ethanol is increased.
在三组大鼠中评估了乙醇训练剂量对选择性5-羟色胺1（5-HT1）激动剂TFMPP（间三氟甲基苯基哌嗪）产生类似乙醇辨别刺激效应能力的影响。这三组大鼠采用双杠杆程序，在固定比率20（FR 20）的食物强化条件下，接受训练以区分1.0 g/kg（n = 5）、1.5 g/kg（n = 6）或2.0 g/kg（n = 7）的乙醇（灌胃给药）与水。三组的乙醇泛化梯度相当，表明不同训练剂量下乙醇刺激的效力差异不大。然而，TFMPP（0.1 - 1.7 mg/kg；腹腔注射）替代乙醇的能力取决于训练剂量。TFMPP在1.0 g/kg组导致部分替代，在1.5 g/kg组完全替代，而在2.0 g/kg乙醇训练组中无替代作用。结果表明，中等剂量乙醇的辨别刺激效应存在5-羟色胺能成分，随着乙醇剂量增加，该成分并不突出。这些数据进一步支持了乙醇产生混合辨别线索的假说，即当乙醇剂量增加时，其各成分并非均一地增强。
