Conditioned Placed Preference Experiment On Rat Using Odor Cue As Conditioned Stimulation

Object:Experiment box of Conditioned placed preference(CPP) can provide many kinds of cue-conditioned stimulation such as olfaction,vision and touch.People generally use more cues-conditioned stimulations for maximum distinguishing the two experiment boxes environments.But there is one trouble of cues-conditioned stimulations:which one cue-conditioned stimulation forms contact with drug reward or combination of various stimulations form contact with drug reward.Therefore,it might be better to use single cue-conditioned stimulation than more cues-conditioned stimulations for some experiment reserches.The experiment is one CPP experiment on rat by the only odor cue as conditioned stimulation (CS),the purpose of it is to analyse the role of odor as a single CS.Method:In this paper, adult Sprague Dawley (SD) rats were randomly divided into corresponding odor group.opposite odor group and no-odor group. Experimental system is composed of CPP box and video record device. CPP box is composed of two behavior boxes of the same size and an intermediate box. there is a bottle with rose or mint pentration in the corner of each behavior box.Except odor, the two behavior boxes are identical. Video recording system is composed of camera placed at the top of the CPP box and computer software system. The experiment is composed of three stages. The first stage is pre-conditioning phase. On lth-3th, everyday rats were allowed to move free in CPP box for 15 minutes(900 seconds) and were recorded completely by the video record device. Then rats were put into 3 identical rooms for 3 hours by 3 groups respectively.The second phase is conditioning phase,4th-11th, a total of 8 days. It was to choose one odor as positive odor in rose and mint randomly. Each rat of morphine group received four saline and four morphine pairings on alternating days, and was placed into the assigned chamber for 45 minutes. The neutral zone was never used during conditioning and was blocked by guillotine doors. Then the rats were put into 3 rooms with different odor for 3 hours respectively. The rats of saline groug were dealed with same processing except only injected saline everyday. The third stage is test phase. Everyday rats were allowed to move freely in CPP box for 15 minutes(900 seconds) and were recorded completely by the video record device.Data analysis method:The data was derived from the times(second) of rats staying in the positive odor box. The paper used One-way AN OVA and Repeated Measures analysis of SPSS 11.5.Result:In pre-conditioning phase, the times of each group rats in positive odor box are not statistically significant(p>0.05).In test phase, the times of each group rats in positive odor box are not statistically significant(p>0.05).Conclusion:The CPP on rats by the only odor cue as CS is not established, it might be concerned with the odor concertration, which is difficult to control.