ABSTRACT
Resumen En esta investigación se evaluaron los efectos de la administración sistémica del antagonista GABAA bicuculina sobre los efectos del agonista 5-HT1A 8-OH-DPAT en las propiedades discriminativas de la anfetamina (ANF) utilizando el condicionamiento de aversión a los sabores. Los resultados mostraron que ni el 8-OH-DPAT, ni la bicuculina, sustituyeron la señal discriminativa de la ANF. Sin embargo, la administración del 8-OH-DPAT disminuyó la señal discriminativa de la ANF, y la administración de la bicuculina, previa a la administración del 8-OH-DPAT más una dosis de ANF, previno el efecto del 8-OH-DPAT sobre la señal discriminativa de la ANF. Estos datos apoyan la hipótesis de que las conductas relacionadas con la adicción a las drogas, como la ANF, involucran diferentes sistemas de neurotransmisión como la DA, la 5-HT y el GABA.
Abstract In this research, the effects of systemic administration of the GABAA receptor antagonist bicuculline on the effects of 5-HT1A receptor agonist 8-OH-DPAT on the discriminative properties of the AMPH using the conditioned taste aversion procedure were evaluated. The results showed that neither 8-OH-DPAT nor bicuculline administration did not substitute for AMPH. However, the 8-OH-DPAT administration decreased the discriminative signal of AMPH and the bicuculline administration, prior to the 8-OH-DPAT administration plus a dose of AMPH prevented the effect of the 8-OH-DPAT on discriminative signal of AMPH. These data support the hypothesis that addiction-related behaviors of drugs such as AMPH involve several neurotransmitter systems such as DA, 5-HT and GABA.
ABSTRACT
ObjectiveTo evaluate the discriminative stimulus effects of nicotine on the basis of a rat model of heroin discrimination.MethodsMale Sprague-Dawley rats were trained to discriminate 0.3 mg/kg heroin from saline under a fixed-ratio (FR10) schedule of food reinforcement.After training,different doses of heroin and nicotine were used to substitute for training dose of heroin,the dose-response curve for heroin and the discriminative stimulus effects of nicotine were identified in rats.ResultsAll rats reliably discriminated 0.3 mg/kg heroin from saline.Different doses of heroin ( 0.03,0.1,0.3,0.56 mg/kg ) produced ( 33.9 ± 15.0 ) ％,( 43.3 ± 13.3 ) ％,(98.7 ± 0.5 ) ％,(99.4 ± 0.2 ) ％ total responding on heroin associated lever,heroin at the doses of lower than 0.3 mg/kg produced the dose-dependent relationship in heroin-appropriate responding.In heroin-trained rats,nicotine at the dose of 0.03,0.1 mg/kg produced(1.9 ±1.1)％,(13.7 ±5.6)％ total responding on heroin associated lever,there were extremely significant differences with 0.3 mg/kg heroin control (P＜0.01).However,nicotine at the dose of 0.3,0.5 mg/kg produced ( 60.4 ± 16.1 ) ％,(65.9 ± 16.4) ％ total responding on heroin associated lever,there were no significant differences with 0.3 mg/kg heroin control (P＞ 0.05 ).ConclusionNicotine at the dose of 0.3,0.5 mg/kg can partially produce heroin-like discriminative stimulus effects.