Empirical Study Of The Protection Effect Of PAF-R Antagonist (TMP) On Bone Of Rats Performed By Ovariectomy

Objective:Based on establishing the model of rats performed by ovariectomy due to the lack of estrogen, using TMP therapy, the method of immunohistochemistry and bonemineral density(BMD) to examine the BMD of vertebra and femur and Expression of NF-kB in the vertebra of Lumbar spine. Use the process of Enzyme-linked Immunosorbent Assay (ELISA) and microscope to observe the indicators of Biochemical and bone resorption and the changes of vertebral microstructure. To observe the influence of TMP on bone quality of ovariectomized rats,and to study the possible mechanism.Methods:The animal model was established with female SD rats. The 48 SD rats were randomly divided into 6 group: A group: sham operation (sham)group; B group: ovariectomized(OVX)group; C group: OVX treated with small dose TMP group; D group: OVX treated with mean dose TMP group;E group: OVX treated with large dose TMP group; F group : OVX treated with ERT group, with 8 animals in each group. From the one week after operation, A group and B group was performed Intraperitoneal injection with normal saline 2ml every day; C group was performed Intraperitoneal injection with TMP 50mg/kg every day; D group was performed Intraperitoneal injection with TMP 100mg/kg every day; E group was performed Intraperitoneal injection with TMP 200mg/kg every day; F group was performed intramuscular with Estradiol Benzoate(E2)1mg EOD, the course of treatment was 4 weeks, 8weeks, 12weeks, the ALP, BALP, TRACP-5b, PAF and bone density were tested. and the histomorphology of bone was disposaled by H-E staining and the NF-kB expression by immunohistochemistry staining.Results:Establish animal model of rats imitating post-menopause wemen succesfully by ovariectomy. The PAF, ALP, BALP, TRACP-5b of OVX group were higher than sham group(P<0.01~0.05).The bone density of OVX group were lower than sham group(P<0.01~0.05). All parameters referred in therapeutic groups presented significant differences compared with those in OVX group(P <0.001),large dose TMP therapeutic group especially.(2)The gray scale of NF-kB expression was higher in OVX group than sham group(P <0.01),and the bone trabeculae in OVX group became thinner and gaps became wider compared with sham group; the gray scale of NF-kB expression was lower in therapeutic groups compared with OVX group(P<0.05, P<0.01, P<0.001), All parameters referred in therapeutic groups presented significant differences compared with those in OVX group,and the bone trabeculae in therapeutic group became thickening and gaps became smaller and bone microstructure improving significantly compared with OVX group(P <0.001).Conclusion:We consider that TMP could protect OVX rats from osteoporosis,and this protection is related with the reduction of PAF or inhibition combination of PAF and PAFR and the expression of NF-kB.