Becker Guillaume, Lespine Louis-Ferdinand, Bahri Mohamed Ali, Serrano Maria Elisa, Lemaire Christian, Luxen André, Tirelli Ezio, Plenevaux Alain
GIGA-Cyclotron Research Center-In Vivo Imaging, University of Liège, 4000 Liege, Belgium.
Department of Psychology, University of Liège, 4000 Liege, Belgium.
Brain Commun. 2021 Dec 15;4(1):fcab294. doi: 10.1093/braincomms/fcab294. eCollection 2022.
Wheel-running exercise in laboratory rodents (animal model useful to study the neurobiology of aerobic exercise) decreases behavioural markers of vulnerability to addictive properties of various drugs of abuse including cocaine. However, neurobiological mechanisms underpinning this protective effect are far from fully characterized. Here, 28-day-old female C57BL/6J mice were housed with ( = 48) or without ( = 48) a running wheel for 6 weeks before being tested for acute locomotor responsiveness and initiation of locomotor sensitization to intraperitoneal injections of 8 mg/kg cocaine. The long-term expression of sensitization took place 3 weeks after the last session. On the day after, all mice underwent a micro-PET imaging session with [F]fallypride radiotracer (dopamine 2/3 receptors antagonist). Exercised mice were less sensitive to acute and sensitized cocaine hyperlocomotor effects, such attenuation being particularly well marked for long-term expression of sensitization ( = 0.262). Chronic administration of cocaine was associated with a clear-cut increase of [F]fallypride binding potential in mouse striatum ( = 0.170) while wheel-running exercise was associated with a moderate decrease in dopamine 2/3 receptors density in striatum ( = 0.075), a mechanism that might contribute to protective properties of exercise against drugs of abuse vulnerability.
实验室啮齿动物的转轮运动（一种有助于研究有氧运动神经生物学的动物模型）可降低对包括可卡因在内的各种滥用药物成瘾特性的易感性行为指标。然而，支撑这种保护作用的神经生物学机制远未得到充分表征。在此，将28日龄的雌性C57BL/6J小鼠分为两组，一组（n = 48）配备转轮，另一组（n = 48）不配备转轮，饲养6周，然后测试它们对腹腔注射8 mg/kg可卡因的急性运动反应性以及运动敏化的起始情况。敏化的长期表达在最后一次给药后3周进行。在次日，所有小鼠都接受了使用[F]氟哌利多放射性示踪剂（多巴胺2/3受体拮抗剂）的微型PET成像检查。运动的小鼠对可卡因引起的急性和敏化性运动亢进效应较不敏感，这种减弱在敏化的长期表达中尤为明显（p = 0.262）。长期给予可卡因与小鼠纹状体中[F]氟哌利多结合潜能的明显增加相关（p = 0.170），而转轮运动与纹状体中多巴胺2/3受体密度的适度降低相关（p = 0.075），这一机制可能有助于运动对滥用药物易感性的保护作用。
