Sasaki T
Histochemistry. 1984;80(3):263-8. doi: 10.1007/BF00495775.
Using horseradish peroxidase (HRP) as a soluble protein tracer, electron microscopic studies were carried out in order to analyze endocytosis in the ruffle-ended ameloblasts of rat incisors. Accumulated HRP was initially incorporated from the ruffled border into the cytoplasm by means of pinocytic vacuoles ( pinosomes ) and pinocytotic coated vesicles. The majority of the HRP was taken up by the large number of pinosomes , which then formed large endocytotic vacuoles by fusing either with each other or with preexisting endocytotic vacuoles. As time passed HRP accumulated, not in the pinosomes and ruffled border but in the endocytotic vacuoles and multivesicular bodies. Frequent connections between HRP-labeled coated vesicles and these cytoplasmic bodies indicate that these vesicles serve as an HRP carrier. These findings strongly suggest that ruffle-ended ameloblasts actively absorb soluble proteins from the enamel matrix during enamel maturation.
使用辣根过氧化物酶（HRP）作为可溶性蛋白质示踪剂，进行了电子显微镜研究，以分析大鼠切牙褶缘成釉细胞的内吞作用。积累的HRP最初通过胞饮泡（胞饮体）和有被胞饮小泡从褶缘进入细胞质。大部分HRP被大量的胞饮体摄取，这些胞饮体随后通过彼此融合或与预先存在的内吞泡融合形成大的内吞泡。随着时间的推移，HRP不是在胞饮体和褶缘积累，而是在内吞泡和多泡体中积累。HRP标记的有被小泡与这些细胞质体之间频繁的连接表明这些小泡作为HRP载体。这些发现强烈表明，褶缘成釉细胞在釉质成熟过程中积极地从釉质基质中吸收可溶性蛋白质。
