Köling A
Department of Otolaryngology, Uppsala University, Sweden.
Arch Oral Biol. 1987;32(3):153-8. doi: 10.1016/0003-9969(87)90127-0.
Replica preparations of dental pulp revealed membrane specializations indicating both exocytosis and endocytosis in the apical part of the odontoblast cell body and the proximal part of the odontoblast process. In tangential fractures, the plasmalemma exhibited protruding spheroids, considered to be the final stage in exocytosis. Other stages observed were plasmalemmal elevations covering underlying vesicles and surrounded by particle-free zones and fusion between vesicles and the cell membrane. Features indicative of endocytosis were plasmalemma studded patchwise with small circular craters 60-70 nm in diameter, often in association with intramembranous particles, and clusters of particles, probably constituting the sites of initiation of endocytotic vesicles in the plasmalemma.
牙髓的复制品显示,在成牙本质细胞体的顶端部分和成牙本质细胞突起的近端部分,膜特化表明存在胞吐作用和内吞作用。在切向骨折中,质膜呈现出突出的球体,被认为是胞吐作用的最后阶段。观察到的其他阶段包括覆盖在下面囊泡上并被无颗粒区包围的质膜隆起,以及囊泡与细胞膜之间的融合。内吞作用的特征是质膜上有直径60 - 70纳米的小圆形凹坑,呈斑块状分布,通常与膜内颗粒有关,还有颗粒簇,可能构成质膜内吞小泡的起始部位。