The Correlation Study Between Bisphosphonate Application And Bone Marrow Of Miniature Pig

Objective: To investigate the variaion rule of miniature bone marrow of miniature pig after bisphosphonate injection from vein of ear,make sure the variation of bone marrow hyperplasia degree clinic meaning for Bisphosphonates-related Osteonecrosis of the Jaw,which can provide the information for the therapeutic mechanism of Bisphosphonates-related Osteonecrosis of the Jaw and make sure to discover the disease as soon as possible.Subjects and Methods: 1.Nine miniature pigs were divided into two groups randomly: treatment group and control group:6 for treatment group and 3 for control group. Every miniature pig is healthy and age from 8 month to 12 month, and from the same unit.In order to make sure animals adapting the environment of the laboratory when begin the experiment. Zometa were injected in treatment group with 4.0mg every two weeks from the vein in the edge of ear, 10 doses in total, the first mandibular premolar wereextractedin 8th week to generate the bone osteonecrosis model. Normal saline were injected in control group 100ml every two weeks from the vein in the edge of ear, 10 doses in total as control, the mandibular first premolar were extracted as well. 3. Bone marrow of each animal were aspirated and smears and sections were made at 0th week ,8th week ,16th week and after bone osteonecrosis. 4. All datas were collected into Excel, statistic analysis were made by SPSS 16.0 software. The comparison between various mean were analyzed by single factor analysis of variance, the mean between various groups were analyzed by LSD,Dunnet T method. A probability value of P<0.05 was considered statistically significant.Results: In treatment group, after Zometa injection from the vein in the edge of ear, and extraction of the fisrt mandibular premolar in 8th week to found the bone osteonecrosis model, osteonecrosis were found in 3 miniature pigs, the successful rate is 50%. In treatment group's bone marrow smear, bone marrow hyperplasia degree of animals decreased at 8th week, meanwhile it improved slowly at 16th week, 24th week and after bone osteonecrosis but which is still below the normal level. The difference of the treatment groups at the same time was not significant (P>0.05); The difference of the control groups at the same time was not significant (P>0.05); every cell series in all treatment groups are not significant (P>0.05); In treatment group's bone marrow section, bone marrow hyperplasia degree of animals decreased at 8th week, meanwhile it improved slowly at 16th week, 24th week and after bone osteonecrosis but which is still below the normal level. The difference of the treatment groups at the same time was not significant (P>0.05); The difference of the control groups at the same time was not significant (P>0.05).Conclusion: After bisphosphonate injection, bone marrow hyperplasia degree of miniature pig decreased. The experimental data suggest bone marrow hyperplasia degree of animals decreased at 8th week, meanwhile it improved slowly at 16th week, 24th week and after bone osteonecrosis but which is still below the normal level. But the number of animal is less, and experimental time is short, so we need to a further study.