Abstract: Social interaction is a substantial natural reward. Similar to drug-induced conditioned place preference (CPP), social reward-CPP is established via a Pavlovian association between the environment and the rewarding effects of social interaction. Socially monogamous mandarin voles (Microtus mandarinus) engage in a suite of close social interactions that include parent-offspring bonding; like females, males also provide high levels of parental care to pre-weanling pups. The reinforcing property of pups in parents is known. However, it remains unclear whether parents could become reinforcing to pre-weanling pups. To evaluate the reward associations that pre-weanling pups formed with their parents, the CPP response to dams, sires and a pharmacologic reinforcer (cocaine, 20 mg/kg) was assessed in postnatal day (PND) 13-17 and PND 19-23 mandarin vole pups. We found that the time that the pups spent in the reinforcing agent-paired chamber and opposite chamber of the apparatus was not statistically differences whether conditioned to dams, sires or cocaine respectively. These results indicate that pre-weanling mandarin vole pups failed to form place preferences to their fathers, mothers, or cocaine (at the doses tested).

Key words: Cocaine, Conditioned place preference, Mandarin vole, Social reward

摘要： 个体间的社会互作是一种天然奖赏，这种社会性奖赏诱导的条件位置偏爱（Conditioned place preference, CPP）是通过环境信息和社会互作奖赏效应间建立条件反射形成的，与药物奖赏诱导的CPP相似。棕色田鼠 (Microtus mandarinus) 是一种社会性单配制田鼠，具有紧密的亲-子联系和社会互作；雄鼠对断乳前幼仔也提供较高水平的亲本抚育。幼仔强化能够诱导母鼠及父鼠形成CPP，但双亲对幼仔是否也具有强化效应还不清楚。为探讨断乳前幼仔与双亲形成的奖赏联系，本实验检测了出生后13-17d 和19-23d 两个发育龄段的棕色田鼠幼仔对母鼠、父鼠以及可卡因 (20 mg/kg) 的CPP反应。数据显示在分别用母鼠、父鼠或可卡因强化后，两个龄段的幼仔在CPP箱的强化室与非强化室所处时间没有显著性差异。这些结果表明断乳前棕色田鼠幼仔不能形成对母鼠、父鼠及可卡因的位置偏爱。

关键词: 棕色田鼠, 社会性奖赏, 可卡因, 条件位置偏爱