The aim of the present study was to examine changes in pain perception in different times after bile duct ligation (BDL) in rats. Male Wistar rats weighing 250-300 (g) were used. Then, changes in pain perception of three experimental groups including control, sham and rats with BDL were examined using a hotplate test on 1, 2 or 3 weeks after the bile duct ligation. The result showed that there was no difference in pain perception between control and sham groups on 1, 2 or 3 weeks. In addition, pain tolerance after one week in BDL rats, putatively was increased but it was not significant. However, pain tolerance in BDL group compared to sham control group was significantly increased on 2 and 3 weeks after BDL. It can be concluded that BDL may result in increase of opioids in the body, and this increase on two week after BDL may reach a level in which an analgesic effect can be measured by hotplate test.
