Lyroudia K, Economou L, Manthos A, Zervas P, Albanou A, Foroglou C
Department of Dental Pathology and Therapeutics, Aristotelian University of Thessaloniki, Macedonia, Greece.
Histol Histopathol. 1993 Apr;8(2):227-34.
Dental pulp capillaries were studied in human. They were of the continuous type, with the exception of a small number which were of the fenestrated type, located in the vicinity of the odontoblasts. A characteristic morphological peculiarity was found in the endothelial cells. In places there was a large quantity of multi-sized vacuoles. The vacuoles were evidently of pinocytotic origin, and their content was emptied into the extracapillary space. The initiation of their formation was indicated by the creation of cytoplasmic flaps, which could not be characterised as typical pseudopodia, and which in cross sections resembled microvilli. The flaps engulfed a quantity of plasma and then, after bending over, their edge fused with the cell, creating a vacuole. The vacuole, after being moved abluminally, was emptied into the pericapillary area by exocytosis. There was indication that flaps created at the borders of the endothelial cells (flanges) acted likewise, transporting vacuoles through the intercellular spaces. Micropinocytosis, was a distinctly different phenomenon, contributing, to a very small degree, to the intracellular enlargement of the vacuoles. It seems that this vacuolar mechanism of transportation serves an augmented metabolic need of the surrounding tissue.
对人类牙髓毛细血管进行了研究。它们属于连续型，只有少数位于成牙本质细胞附近的为有孔型。在内皮细胞中发现了一种特征性的形态学特性。有些部位有大量大小不一的空泡。这些空泡显然起源于胞饮作用，其内容物被排空到毛细血管外间隙。其形成的起始表现为细胞质瓣的产生，这些细胞质瓣不能被定性为典型的伪足，在横切面上类似微绒毛。这些瓣吞噬了一定量的血浆，然后在弯曲后，其边缘与细胞融合，形成一个空泡。空泡向远离管腔侧移动后，通过胞吐作用被排空到毛细血管周围区域。有迹象表明，在内皮细胞边界处形成的瓣（边缘）也有同样的作用，通过细胞间隙运输空泡。微胞饮作用是一种明显不同的现象，对空泡的细胞内扩大作用极小。看来这种空泡运输机制满足了周围组织增加的代谢需求。
