血小板衍生生长因子-AA对破骨细胞功能的影响

目的　研究血小板衍生生长因子 (PDGF) AA对破骨细胞功能的影响。　方法　利用免疫电镜技术证明PDGF α受体在破骨细胞膜得以表达 ;酶动力学法测定培养基中酸性磷酸酶与抗酒石酸酸性磷酸酶活性 ;通过荧光探针在共聚焦显微镜下观察破骨细胞内氢离子随PDGF AA浓度的变化情况 ;利用甲苯胺蓝对骨吸收陷窝染色并在图像分析仪下测定其面积和数目。　结果　破骨细胞膜有胶体金颗粒沉着 ,抗酒石酸酸性磷酸酶的活性无显著变化 (P >0 0 5 ) ,细胞内氢离子显著增加 ,但PDGF AA不能促进其释放 ;骨吸收陷窝的面积与数目均无显著变化。　结论　PDGF AA虽然能够促进氢离子在细胞内产量增加 ,但由于不能显著改变抗酒石酸酸性磷酸酶活性 ,因而不能直接促进破骨细胞的骨吸收功能。

The effects of platelet-derived growth factor-AA on the osteoclasts

OBJECTIVE: To study the effects of platelet-derived growth factor (PDGF)-AA on the osteoclasts. METHODS: The PDGF receptor alpha (PDGFR-alpha) was detected on the osteoclastic membrane with immunoelectronmicroscopy. Acid phosphatase (ACP) and tartrate-resistant acid phosphatase (TRAP) activities were measured kinetically and the introcellular hydrogen ions were calculated on the confocal laser scanning microscope (CLSM) stained with SNAFL. Stained by toluidine blue, the area and number of the resorption pits were determined with the Leica Quantimet 500 system. RESULTS: The colloidal gold precipitated on the cellular membrane, and the TRAP activity had no difference (P > 0.05). Hydrogen ions rose significantly but their release could not be promoted by PDGF-AA. The changes of the resorption pits were not significant. CONCLUSIONS: The PDGF-AA could promote hydrogen ions yielding but not stimulate osteoclastic bone resorption due to the significant TRAP changes of TRAP activities.