抄録
Schwann cell basal laminae of mouse sciatic nerve were studied histochemically using tannic acid (TA) and ruthenium red (RR) in tissue sections. In addition, basal laminae isolated by sonication were examined using ferritin-conjugated lectin for carbohydrate residues and by immunohistochemistry for laminin. Isolated basal laminae were also examined by RR. The outer (interstitial) surface of the basal laminae were observed by scanning electron microscopy (SEM).
By TA staining, the basic lattice-like structure of lamina densa was revealed, and fine and thick filamentous fuzzy structures were seen to project from both sides of this lattice.
By RR staining, there were dark-stained spots of proteoglycans, arranged at 30-100 nm intervals, on the outer surface of the basal lamina. These spots are considered to be primarily responsible for the attachment of basal lamina to the surrounding connective tissue matrix.
Out of 12 lectins examined, WGA, RCA-I and ConA bound to the isolated basal laminae: WGA tended to bind to the inner surface, while the other two lectins bound almost equally to both sides.
Laminin appeared to be more abundant on the inner surface than on the outersurface of the basal lamina.
SEM revealed a somewhat fuzzy but unexpectedly smooth outer surface of basal lamina. There were small pits scattered randomly on the basal lamina.
These findings are discussed from the point of view of the polarity of the basal lamina, and its role in cell adhesion to the surrounding extracellular matrices.
