Über den komplexen Bau der Membranen des Bindegewebes von Insekten

Abstract

The connective tissue sheeth around the nervous system of the cockroach and the silkworm moth is a heterogeneous and complicated structure. Microscopically one can detect small fibers, both longitudinal and circumferential, which are embedded in a seemingly non-fibrous matrix. Analysis of the optical properties with polarized light gave imbibition curves of unusual shape implying a relatively dense packing of micelles or crystallites. Tests showed recovery of length after stretching more than 100 per cent. This elasticity is accompanied by a strain birefringence that is both too great and too complicated to be explained as being due simply to improved alignment of the microscopically visible fibrils. X.ray diffraction diagrams prepared by Dr. K. M. RUDALL show the presence of the 2,86 A line considered to be characteristic of collagens, but the intensity of this line implies a collagen concentration of only 10 — 20 per cent. Optical properties imply the presence of a lipid component. Staining and solubility properties are mostly similar to the collagenous proteins but do not agree completely with either collagen (stricto sensu), elastin or reticulin of vertebrates. The imbibition curves, the elasticity, and the strain birefringence are not consistent with the known properties of the collagegenous proteins—presumably these are due to the not yet identified protein or mucoprotein that makes up the bulk of the neural lamella and confers distinctive properties upon insectan connective tissue.