Table 1: Primo nodes and vessels in the surroundings of the peripheral and central nervous system.

AreasSpecies and sitesDyes

3rd or 4th ventriclesRat [3, 4]; rabbit [5, 6]Fluorescent nanoparticles, hematoxylin, Acridine orange, propidium iodide, DiI, Perchlorate, DAPI, and yoyo1
Central canal of the spinal cordRabbit [5, 6]Hematoxylin, Acridine orange, propidium iodide, DiI, Perchlorate, DAPI, and yoyo1
Subarachnoid spaceRat [3] and pig [7] spinal cords; rat brain [4]Fluorescent nanoparticles, DAPI, and Phalloidin
Venous sinusRat cerebrum [8]Chromium hematoxylin and DAPI
Surroundings of the brainRat cerebrum [9], pineal body [9], and spinal cord [4, 9]; rat [4, 9] and rabbit [10] cerebellumsAlcian blue, DAPI, trypan blue, Phalloidin, and DAPI
Surroundings of the peripheral nerveEpineurium, perineurium, or endoneurium in rat sciatic nerve [4, 11]Fluorescent nanoparticles and DAPI

Technical notes for dyes: DAPI, for nuclei; Phalloidin, for nuclei and F-actin; Acridine orange, for DNA particles; Propidium iodide, for nucleus and F-actin; DiI, for membrane phospholipid; Perchlorate, for microparticles inside the nerve primo vessel; Fluorescent nanoparticles, cobalt-ferrite embedded in silica shells with rhodamine B as a contrast agent during MRI.