PERMANENT ELECTRIC POLARIZATION OF MENINGES OF MAN

Two directions of permanent electric polarization are demonstrable in the human meninges; they can be clearly distinguished by appropriate measurements. The first direction of polarization runs parallel to the longitudinal direction of the collagen fibrils in these structures and is particularly marked in the meninges of the spinal cord. The spinal dura mater, the spinal arachnoidea and the spinal pia mater are characterized by having a longitudinal polarization whose direction is identical in the three meninges, and which continues uninterrupted from the cranial starting point of these structures to their caudal end point. The direction of longitudinal polarization in the sheaths of the human spinal cord corresponds to that found in lower vertebrates (Petromyzon, Acipenser) and is probably a uniform feature of all Vertebrata. The direction of longitudinal electric polarization in the human spinal dura mater has its direct continuation, without any directional changes, in the longitudinal polarization of the epineurium of the sacral plexus, the N. ischiadicus, and then the N. tibialis and the N. fibularis communis. The meninges exhibit their second direction of polarization between the external and the internal surfaces, i.e. at right angles to the course of the collagen fibrils. An attempt was made to elucidate the principle underlying this direction of polarization. For this purpose, we also carried out comparative studies on aponeuroses (Bos taurus) and the swimming-bladder capsule of carp. On the basis of X-ray diffraction patterns and the anisotropy established in swelling experiments, it is assumed that a preferred electric direction is in the ultrastructure of the collagen fibrils at right angles to their longitudinal axis. It is further assumed that in the morphogenesis of collagen, the fibrils of certain tissue structures are aligned in such a way that the longitudinal as well as the transverse fibril axes are arranged in a parallel pattern. In this way the two electrical axes of the supportive protein, collagen, are directly interrelated with the morphological axes (e.g. cranial/caudal, dorsal/ventral or outward/inward) in the body of organisms. The relationship possibly existing between permanent electric outside-inside polarization and selective permeability (diffusion barrier") in these structures is discussed briefly. © 1969 Springer-Verlag."