Osteoblastlarda Anti-Apoptotik ve Proliferatif Etkili Adrenomedüllin Hormonunun Segmental Kemik Defekti Üzerine Etkisi

Abstract

Orthopaedic treatment of bone defects is difficult and costly. Animal researches with bone defects are used to investigate the effects of many molecules and biomaterials. We planned an animal research to investigate the effect of adrenomedullin hormone, which has been found in recent years and whose effects are not yet fully understood, on bone defect. We tried to find an answer whether adrenomedullin hormone with its positive effects on bone tissue both at the macroscopic and cellular levels can contribute to the improvement of segmental bone defect. Time and dose dependent six groups were created with 36 Wistar rats. In each group, a 2 mm defect at the diaphysis of radius was created bilaterally. NaCl solution was administered to sham groups three times a week for 4 and 8 weeks, intraperitoneally. Adrenomedullin was administered to experiment groups three times a week; 15 µg 4 weeks, 15 µg 8 weeks, 30 µg 4 weeks and 30 µg 8 weeks. At the end of the experiment, the animals were euthanized and the defect site was visualized by microtomography in the formolin solution. After that, histological analysis was performed and new bone areas formed in defect area was measured via light microscope. Microtomographical and histological data between groups were compared using statistics. In microtomography and histology, it was observed that there were statistically significant in some of the parameters indicating new bone formation in 15 µg groups and bone mineral density was found higher in adrenomedullin groups. Conclusion: In our study, although there is no statistically significant difference in most parameters, there are radiological and histological results that indicate adrenomedullin may have a positive effect on damaged bone tissue at certain doses. However, this effect did not reveal as great improvement in a bone defect model. Further studies are needed on how adrenomedullin and calcitonin group hormones affect bone tissue in cases of trauma or stress.