Radially oriented astrocytes in the normal adult rat spinal cord

Glial cell organization in the adult rat spinal cord was studied using a modified Golgi technique and anti-GFAP immunofluorescence. Gray matter astrocytes appeared to be a homogeneous population, while in white matter, two morphologically distinct astrocyte subpopulations were seen. One astrocyte had the morphological characteristics of classically described fibrous astrocytes. However, the predominant astrocyte was a radially oriented cell which appeared to span the white matter from the pial surface to the gray-white interface.