Morphological analysis of intranuclear bFGF

本研究旨在探讨核内碱性成纤维细胞生长因子在小脑浦肯野细胞发育、再生肝细胞和成肌细胞中的作用。1.浦肯野细胞的发育。出生后7天，小脑皮质可见免疫反应阳性的浦肯野细胞，主要在顶端胞浆和近侧树突表达bFGF样免疫反应。出生后14天至28天，浦肯野细胞胞浆和胞核均可见bFGF样免疫反应。统计分析显示，出生后第21天，胞核bFGF免疫反应阳性的浦肯野细胞达到高峰。2.再生肝细胞bFGFI免疫印迹实验和ELISA法显示，再生肝部分切除48h后再生肝细胞核亚细胞成分中bFGF的高分子量一过性增加。光镜下碱性成纤维细胞生长因子和增殖细胞核抗原免疫反应…肝切除组大鼠肝细胞核内可见较多的ES。电子显微镜显示bFGF样免疫反应主要见于核内常染色质，极少数见于再生肝细胞的异染色质或核仁中。3.碱性成纤维细胞生长因子的成肌活性。用免疫印迹分析和电子显微镜观察bFGF样免疫反应在生后28天营养不良的mdx小鼠咬肌中的分布。在电子显微镜下，在小的再生心肌细胞中可检测到碱性成纤维细胞生长因子的免疫反应，成熟的肌细胞中有密集的肌丝，但未见碱性成纤维细胞生长因子的免疫反应。研究碱性成纤维细胞生长因子和血小板第4因子(PF4)阻断碱性成纤维细胞生长因子与其受体结合对成肌细胞培养的影响。生物特异性相互作用分析(BIA)核心系统显示，成肌细胞膜组分中含有可被PF4阻断的bFGF结合元件。较少

This project was performed to investigate the function of intranuclear bFGF in developing cerebellar Purkinje cell, regenerating hepatocyte and myoblast.1.Development of Purkinje cells with bFGFGOn postnatal day 7, immunoreactive Purkinje cells were identified throught cerebellar cortex, and they expressed bFGF-like immunoreactivity mainly in the apical cytoplasm and proximal dendrites. From postnatal day 14 to postnatal day 28, bFGF-like immunoreactivity was noted throughout the cytoplasm and nuclei of Purkinje cells. Statistical analysis showed that Purkinje cells with nuclear bFGF-immunoreaction peaked on postnatal day 21. After postnsl day 42, Purkinje cells with nuclear nFGF showed a marked decrease in number.2.Regenerating hepatocytes with bFGFImmunoblot experiments and ELISA showed a transient increase in high-moleculae-weight froms of bFGF in the nuclear subcellular fraction of regenerating liver 48h after partial hepatectomy. By light microscopy, bFGF and PCNA immunoreactiviti … More es were detected in the nuclei of hepatectomy. Electron microscopy demonstrated bFGF-like immunoreactivity mainly in the nuclear euchromatin and rarely in the heterochromatin or nucleoli of regenerating hepatocytes. These results suggest an important role of the high-molecular-weight forms of bFGF in hepatocyte proliferation and mitosis.3.Myogenic activity of bFGFThe localization of bFGF-like immunoreactivity in the masseter muscle of dystrophic mdx mice on postnatal day 28 was investigated by immunoblot analysis and electron microscopy. By electron microscopy, bFGF immunoreactivity was detected in small regenerating myocytes, and mature myocytes with densely packed myofilaments did not exhibit bFGF immunoreactivity. The effect or bFGF and platelet factor 4 (PF4), which blocks the binding of bFGF to its receptor, on myoblast culture was investigated. bFGF stimulated myoblast proliferation and myotube formation, but PF4 inhibited these effects of bFGF.The biospecific interaction analysis (BIA) core system showed that the myoblast membrane fraction contains bFGF-binding elements which are blocked by PF4. Less