Sakada S, Sasaki T
Anat Embryol (Berl). 1984;169(3):237-47. doi: 10.1007/BF00315629.
Correlated thin-section, freeze-fracture and tracer examinations were used to examine the blood-nerve barrier of the Vater-Pacini corpuscles in cat mesentery. A laminar inner core and a multilayered outer core enfolded the terminal nerve fiber of the corpuscle. The lamellar cells of both cores were characterized by numerous vesicular membrane invaginations. Freeze-fracture images and tracer experiments employing lanthanum nitrate proved that these invaginations are static structures mediating in neither active pinocytosis nor the transcellular transport of metabolites. In both inner and outer cores, lamellar cells were connected to one another by tight junctions of either the zonula or the fascia type, that occurred between lamellar-cell processes within the lamella and between the cells of adjacent lamellae. Intravascularly applied lanthanum lay at the outermost regions of the corpuscles without entering their internal zones, apparently because lamellar-cell tight junctions hindered further penetration. The results of our investigations suggest strongly that the Vater-Pacini corpuscle lamellae enfolding the nerve terminal form an effective diffusion barrier against the permeation of tissue fluids, thus preserving the corpuscle internal circumference.
采用相关的薄切片、冷冻断裂和示踪剂检查来研究猫肠系膜中帕氏小体的血-神经屏障。一个层状内核和一个多层的外核包裹着小体的终末神经纤维。两个核的板层细胞都有大量囊泡膜内陷的特征。冷冻断裂图像和使用硝酸镧的示踪剂实验证明，这些内陷是静态结构，既不介导活跃的胞饮作用，也不介导代谢产物的跨细胞转运。在内核和外核中，板层细胞通过小带或筋膜型紧密连接相互连接，这些紧密连接发生在薄片内的板层细胞突起之间以及相邻薄片的细胞之间。血管内注入的镧位于小体的最外层区域，未进入其内部区域，显然是因为板层细胞紧密连接阻碍了其进一步渗透。我们的研究结果强烈表明，包裹神经末梢的帕氏小体薄片形成了一个有效的扩散屏障，阻止组织液渗透，从而保护小体的内部环境。
