Construction Of Differential Expression Gene Library Between Normal SD Rat & Ovariectomy Rat And Expression Of Cell Adherent Molecule In Rat's Bone Marrow

Objective: 1. To study variate expressions of cell adherentmolecule-CD44, CD54 FN of cells in corresponding to changesof bone marrow niche after ovariectomy. 2. To study the changes of CD44, CD54, FN expression in bone marrow niche with the effect of estrogen. 3. To detect putative new genes or high specificity differential expression gene related to osteoporosis after menopause, and to construct specific differential expression gene library.Methods: expressions of CD44, CD54, FN of cells in bone marrow on different time after ovariectomy and of cultured cells with single-nucleus in different estrogen concentration were detected using immunohistochemistry assay. The differential expression gene library between normal SD rat and SD rat after ovariectomy was built by SSH (suppression subtractionhybridization), using cells with single-nucleus in bone marrow. Results & Conclusion: It was proved by experiments in vivo that estrogen could influence expression of both CD44 and CD54 of cells in bone marrow. Thus CD44 and CD54 may induce the adhesiveness among monocytes and play a role on fusion of macrophages or formation of osteoclasts. No obvious changes caused by estrogen were observed as to expression of FN of cells in bone marrow. While through experiments in vitro, it was observed that certain concentration of estrogen, at certain time, activated CD44 expression obviously, but under different condition, it suppressed CD44 expression, i. e. as a signal molecular, CD44 showed negative feedback mechanism. It also proved that a certain concentration of CD44 could induce the fusion of monocytes and form osteoclast with multi-nuclei. On the other hand, estrogen showed dose-dependent suppression on expression of CD54 of cells with single-nucleus in bone marrow in vitro and the expression of CD54 was limited to fused .osteoclasts with multi-nuclei, therefore CD54 may take part in formation of osteoclast and adhesiveness of cells. We alsoobserved that estrogen promoted proliferation and differentiation of cultured single-nucleus cells, but it did not show a dose-dependent or time-dependent relationship between estrogen and expression of FN. At last, we adopted the newesttechnique on gene cloning-SSH, to build a differentialexpression gene library between normal SD rat and SD rat after ovariectomy using cells with single-nucleus in bone marrow. It is the base for identification of new differential expression genes related to osteoporosis after menopause with high specificity; these differential expression genes would be candidate genes of occurrence of osteoporosis after menopause.