The research of regeneration, differentiation and the role of fibroblast growth factor in the olfactory system

人们普遍认为嗅觉受体细胞在变性后会再生，也认为在正常情况下动物嗅觉上皮会发生更新。切除后约1个月进行再生。近年来有报道称，干细胞从脑室下区迁移到嗅球室管膜下区是通过嗅觉迁移途径。采用免疫组织化学双染色法研究豚鼠嗅球细胞分裂动力学。检测分裂细胞用抗溴脱氧尿苷（BrdU）抗体，检测神经细胞用抗神经细胞粘附分子，检测神经细胞用抗蛋白基因产物抗体和抗calbindin抗体，检测神经胶质细胞用抗S-100抗体。注射BrdU 1小时后，脑室下区出现大量BrdU标记细胞。brdu标记的细胞在大约1周内通过嗅觉迁移途径从脑室下区迁移到嗅球室管膜下区。然后标记的细胞从球区向周围移动，在一些层中分化出神经细胞和胶质细胞。本研究结果支持足量bFGF在嗅上皮神经发生中起重要作用的观点。bFGF对应用嗅觉细胞的作用还有待进一步研究，但至少发现bFGF对嗅觉细胞分裂活性有影响。

Olfactory receptor cells are widely thought to regenerate after degeneration and also thought to show turnover under normal circumstances in the animal olfactory epithelium. The regeneration is carried out about 1 month after axotomy. Recently it was reported that stem cell migrated from the subventricular zone to the subependymal zone of the olfactory bulb through rostal migratory pathway. We studied cell division dynamics the guinea pig olfactory bulb using immunohistochemical double staining. Anti-bromodeoxyuridine (BrdU) antibody for detecting dividing cells, anti-neural cell adhesion molecule, anti-protein gene product antibody and anti-calbindin antibody, for neural cells, and anti S-100 antibody for glial cells were used immunohistochemical staining.At 1 hour after BrdU injection, many BrdU-labeled cells were present in the subventricular zone. BrdU-labeled cells migrated from the subventricular zone to the subependymal zone of the olfactory bulb through rostal migratory pathway within about 1 week. Labeled cells then moved peripherally from the bulb zone differentiated neural cells and glial cells in some layers.Our results support the idea that an adequate dose of bFGF plays an important role in the neurogenesis in the olfactory epithelium. Further study is needed to clarify the efficacy of bFGF in the applied olfactory cells, but at least bFGF was found to influence to the dividing activity in olfactory cells.