Amizuka N, Yamada M, Watanabe J I, Hoshi K, Fukushi M, Oda K, Ikehara Y, Ozawa H
1st Department of Oral Anatomy, Niigata University School of Dentistry, Japan.
Microsc Res Tech. 1998 May 15;41(4):313-22. doi: 10.1002/(SICI)1097-0029(19980515)41:4<313::AID-JEMT4>3.0.CO;2-R.
Woven bone induced by direct injection of basic fibroblast growth factor (bFGF) into rat bone marrow was examined. On the first day after injection, fibrous tissues formed in the treated region of the bone marrow. Tissue-nonspecific alkaline phosphatase (TNAPase)-immunopositive osteoblastic cells and osteopontin immunopositive-extracellular matrices were observed in the fibrous tissues, indicating bone induction. On the fifth day, the bFGF-induced bone was found broadly in the bone marrow. In the originally existing bone, osteopontin-immunoreactivity was observed at cement lines, but not in the fully calcified matrix, whereas the woven bone displayed immunoreactivity throughout the matrix. Numerous TRAPase-positive osteoclasts were present on the surfaces of the woven bone, but no obvious cement line was observed. Therefore, both bone formation and resorption appeared highly active, without normal cellular coupling equilibrated between bone formation and resorption performed by osteoblasts and osteoclasts. On the tenth day, the bFGF-induced bone was almost replaced by bone marrow. Thus, bone formation actively occurred in the first half of the experimental period, whereas bone resorption came to be predominant thereafter. This study demonstrated that bFGF stimulates bone formation, which, however, is subject to subsequent resorption, probably due in part to the absence of coordinated cellular coupling between osteoclasts and osteoblasts.
研究了将碱性成纤维细胞生长因子（bFGF）直接注入大鼠骨髓所诱导的编织骨。注射后第一天，在骨髓的处理区域形成了纤维组织。在纤维组织中观察到组织非特异性碱性磷酸酶（TNAPase）免疫阳性的成骨细胞和骨桥蛋白免疫阳性的细胞外基质，表明有骨诱导现象。第五天，bFGF诱导的骨在骨髓中广泛出现。在原有的骨中，在黏合线处观察到骨桥蛋白免疫反应性，但在完全钙化的基质中未观察到，而编织骨在整个基质中均显示免疫反应性。在编织骨表面存在大量抗酒石酸酸性磷酸酶（TRAPase）阳性的破骨细胞，但未观察到明显的黏合线。因此，骨形成和骨吸收均表现出高度活跃，而成骨细胞和破骨细胞进行的骨形成和骨吸收之间没有正常的细胞偶联平衡。第十天，bFGF诱导的骨几乎被骨髓取代。因此，在实验期的前半段骨形成活跃，而此后骨吸收占主导。该研究表明，bFGF刺激骨形成，然而，随后会发生骨吸收，这可能部分归因于破骨细胞和成骨细胞之间缺乏协调的细胞偶联。
