A SELECTIVE STAIN FOR RENAL BASEMENT MEMBRANES.

Abstract

Paraffin sections from human kidneys fixed in Carnoy's fluid No. 2 were treated consecutively with periodic acid-sodium bisulfite and stained with resorcin-fuchsin. Basement membranes were colored black in cross sections, dark gray in tangential sections. Cytoplasm, nuclei, reticulin and collagen fibers remained unstained or were only lightly colored, depending on duration of fixation. Elastic fibers were colored black. In sections counterstained with Kernechtrot, the sharp black coloration of basement membranes and the pink staining of nuclei facilitated the study of glomerular lesions. After counterstaining with Van Gieson's picro-fuchsin, the black basement membranes contrasted well with the red reticulin and collagen fibers. Because this method does not require differentiation, it gave uniform results in the hands of different users. No fading was observed in section stored for 3 yr.