The present experiments determined the effects of voluntary home-cage wheel running on the development (Experiments 1 and 2a) and expression (Experiment 2b) of conditioned hyperactivity and long-term sensitization in male, Swiss-Webster mice. Mice experienced 3 weeks of wheel running (exercise) or not (sedentary) either beginning prior to (Experiments 1 and 2a), or immediately following (Experiment 2b), the acquisition phase. During the acquisition phase, mice (n = 12–15/group) received injections (subcutaneous) of either vehicle (saline) or methamphetamine (0.5 or 1.0 mg/kg, Experiment 1; 1.0 mg/kg, Experiments 2a and 2b) immediately prior to 5 locomotor-activity sessions. The extinction phase began 48 hours (h) (Experiment 1) or 3 weeks (Experiments 2a and 2b) after acquisition and all mice received vehicle injections prior to 4 locomotor-activity sessions. Tests of long-term sensitization occurred 72 h after the last extinction session and involved an escalating, methamphetamine-dose regimen (0.25 ➔ 1.0 mg/kg), 1 dose/session for 3 sessions. While pre-acquisition wheel running failed to alter development of conditioned hyperactivity after training with the 0.5 mg/kg methamphetamine dose, it blunted the development of conditioned hyperactivity, and blocked (Experiment 1) or attenuated (Experiment 2a) induction of long-term sensitization after training with the 1.0 mg/kg methamphetamine dose. Furthermore, while post-acquisition wheel running retarded extinction of conditioned hyperactivity, it did not alter expression of conditioned hyperactivity or long-term sensitization (Experiment 2b). Collectively, the results suggest that the impact of voluntary exercise on context-drug associations and long-term sensitization is critically dependent on the timing of exercise relative to drug conditioning.

本实验确定了雄性Swiss-Webster小鼠中主动跑笼运动对条件性过度活跃和长期致敏的发育（实验1和2a）和表达（实验2b）的影响。小鼠在获取阶段之前（实验1和2a）或紧接在（实验2b）之后经历了3周的车轮运动（运动）或不运动（中度）。在采集阶段，小鼠（n = 12-15 /组）立即接受（皮下注射）媒介物（盐水）或甲基苯丙胺（0.5或1.0 mg / kg，实验1； 1.0 mg / kg，实验2a和2b）注射在进行5次运动活动之前。灭绝阶段开始于采集后48小时（h）（实验1）或3周（实验2a和2b），并且所有小鼠在进行4次运动活动之前接受了媒介物注射。上次灭绝后72小时进行了长期致敏试验，涉及逐步升级的甲基苯丙胺剂量方案（0.25➔1.0 mg / kg），每剂1剂，共3次。虽然在以0.5 mg / kg的甲基苯丙胺训练后，采集前轮滑无法改变条件性多动症的发展，但它却使条件性多动症的发展变钝，并阻止了（实验1）或减弱了（实验2a）的长期致敏性的诱导。用1.0 mg / kg的甲基苯丙胺训练后。此外，尽管采集轮运行延迟了条件性多动症的灭绝，它不会改变条件性过度活跃或长期致敏的表达（实验2b）。总体而言，结果表明，自愿运动对情景-药物关联和长期敏感性的影响主要取决于运动相对于药物调理的时机。