The influence of duration of confinement towards morphine dependence intensity in conditioned place preference (CPP) model

• Main Authors: Abdul Basir, Siti Najihah, Suhaimi, Maryam Saadah, Syd Mohmad Faudzi, Syed Mohd Syahmi, Ridzwan, Irna Elina
• Format: Conference or Workshop Item
• Language: English
• Published: 2015
• Subjects: RS Pharmacy and materia medica
• Online Access: http://irep.iium.edu.my/45947/8/PPoint_UCSI_%28N%29.pdf; http://irep.iium.edu.my/45947/

Introduction: Conditioned Place Preference (CPP) continues to be one of the most popular models to study the dependence effects of substance abuse. This study is divided into three main phases which are pre-conditioning, conditioning and post-conditioning phases. It can be conducted using different protocols which can be used to investigate the effects of drug dependence. Since there is not much study done to investigate the effects of duration of confinement, this study is conducted to figure out the effects of different duration of confinement towards intensity of morphine dependence. Methods: Using adult male Swiss albino mice, 12 mice were used for each group with different duration of confinement times, 40 to 60 minutes respectively. During conditioning phase, the mice received 7.5 mg/kg morphine and saline through intraperitoneal route on alternate day for 6 days. Result: Using unbiased method, it was found that both groups had significantly developed dependence (P<0.05, P<0.01). Later, a comparison between these groups had shown that the group of mice that underwent 60 minutes confinement time showed greater intensity of dependence than the other group, although the difference was not statistically significant. Interestingly, it was also noted that the number of mice that was excluded after post-conditioning test was higher in the group that underwent 40 minutes confinement cpmpared to the counterpart (n=5, n=2). Conclusion: These results proved that increasing in confinement time caused an increase in the intensity of morphine dependence in mice. Therefore, it is suggested that 60 minutes confinement time is more suitable for morphine to develop dependence in mice and to minimise subject elimination throughout a long cycle of CPP procedure, provided that other variables are maintained.