The expression of morphine-induced behavioral sensitization depends more on treatment regimen and environmental novelty than on conditioned drug effects

• 来源期刊: 科学通报(英文版)
• 学科: 农学
• 关键词: 药物剂量 空调环境 治疗方案 吗啡 行为 诱导 敏化 CRS
• 年，卷（期）: 2010,（19）
• 所属期刊栏目: Psychology
• 页码范围: 2016-2020
• 页数: 5页
• 分类号: S966.5 TU111.41
• 语种: 英文

摘要

Both conditioned responses(CRs) and sensitized behaviors induced by addictive drugs are considered to reflect drug-seeking motivation.Based on an excitatory conditioning model of behavioral sensitization,this work hypothesizes that conditioned locomotor activity and locomotor sensitization concomitantly occur using different drug treatment regimens.In the present study,conditioned locomotor activity and sensitized locomotion and stereotypy are assessed with pretreatment of two doses of morphine in a familiar or novel environment.When rats are trained with morphine(3 or 5 mg/kg) in an environment to which the animals are habituated,a CR but not contextual sensitization is induced when tested after 1 week of abstinence.When rats receive the 5 mg/kg dose of morphine immediately after placement into a novel environment,the same results are obtained,but when the drug dose is decreased to 3 mg/kg,both the CR and contextual sensitization are observed.Therefore,the sensitized behaviors,rather than the CR produced by morphine pretreatment,appear to be dependent on the drug treatment regimen and environmental novelty,suggesting that different mechanisms may be involved in the expression of the CR and contextual sensitization.