Effect Of Morphine On The Expression Of Osteoclast Associated Cytokine Rankl And Opg In A Mouse Of Bone Cancer Pain

Objective:To establish the rat model of bone cancer pain-morphine tolerance, observe the expression of osteoclast associated cytokine RANKL and OPG.Methods:Select 30 female wistar rats were randomly divided into three groups, Every 10 only divided into a group,the control group(group C) only inject physiological saline in tibia, bone cancer pain group(group B) and bone cancer pain-morphine tolerance group (group BM) both inject nasopharyngeal carcinoma cells in tibia, and subcutaneous injections of physiological saline or morphine. After operation, we observe behavioral changes,measure MWT, weight of rats every, and check the damage of bone with X-Ray on the 14th day after operation, and observe tibial pathologica specimen on 21 days after operation. After the completion of the construction of model, using immunohistochemical to detecte the expression of OPG and RANKL. Results:(1) Behavioral changes:from the 7th postoperative day, group B and group BM rats behavior change, and over time behavior change, the more obvious;group C and animal behavior before and after the surgery, no significant changes in rats. (2) group B and group BM rats from postoperative day 8, the weight is much smaller than in group C (P<0.05).(3)On the 8th day after operation, group B and group BM compared with the group C, the MWT significantly reduced(P<0.05), in the last 3 days of injection of morphine, the MWT of the group BM significantly reduced than the group B (P<0.05).(4) Imageological examination showed that the lateral tibial of group B and group BM appear different degree of bone destruction, but group C has no abnormal. (5) Pathological:rates tibia pathological show,cancer cells in the marrow cavity can be seen on the group B and group BM,the trabecular bone hae been destructioned, group C has no obvious abnormal.(6)The expression of RANKL of BM group is higher than B group, but the expression of OPG is below than B group, the differences have statistical significance (P<0.001).Conclusions:(1) This experiment using the nasopharyngeal carcinoma cells to establish the rat model of bone cancer pain -morphine tolerance. (2) Morphine can upregulate the expression of RANKL,and downregulate the expression of OPG, osteoclast associated cytokine RANKL and OPG may participate in the formation of morphine tolerance mechanism in the rat modle of bone cancer pain.