ABSTRACT

Investigations have demonstrated that circadian rhythm can affect animal curiosity, also a significant correlation has been reported between curiosity and addiction. So the aim of this study is to evaluate the effect of circadian fluctuation in curiosity on addiction. For this purpose, we used the open field (OF) test and conditioned place preference (CPP) biased paradigm. In the OF we evaluated animals curiosity in the morning (ZT 1-2) and in the evening (ZT 11-12). In the CPP, during six training sessions held either in the morning or evening, morphine was injected in a specific compartment. Rats were subsequently tested for preferring the drug-paired chamber at the circadian time that either matched or was different from that of training. The evening rats, compared with the morning groups more spent their time in the center of the OF and also showed a higher preference for staying in the white box in CPP apparatus, and if received morphine at this time, they were conditioned more than morning. The finding of this study showed that the curiosity in rats is higher in the evening and zeitgeber time is more potent for conditioned to morphine than in the morning.

摘要

研究表明，昼夜节律会影响动物的好奇心，据报道，好奇心和成瘾之间存在显着相关性。因此，本研究的目的是评估好奇心的昼夜波动对成瘾的影响。为此，我们使用了开放场 (OF) 测试和条件位置偏好 (CPP) 偏向范式。在 OF 我们在早上 (ZT 1-2) 和晚上 (ZT 11-12) 评估动物的好奇心。在 CPP 中，在早上或晚上举行的六次培训课程中，吗啡被注射到特定的隔间中。随后测试大鼠在与训练匹配或不同的昼夜节律时间更喜欢药物配对室。傍晚的老鼠，与早上组相比，他们更多的时间花在OF中心，也表现出更高的偏好留在CPP仪器的白盒子里，如果此时接受吗啡，他们比早上更有条件。这项研究的结果表明，老鼠的好奇心在晚上更高，而 zeitgeber 时间对吗啡的调节作用比早上更有效。