Rapid Demonstration of Juxtaglomerular Granules in Mammals and Birds

Abstract

Slices of kidney, 3 mm thick, are fixed in 10% formalin containing 5% K2Cr2O7 and 2.5% acetic acid (Smith's fixative) for 18 hr, washed 8 hr in running water, and 6 μ paraffin sections prepared as usual. The sections are brought to water, oxidized 1 min in a 1% KMnO4:1% H2SO4, mixture, decolorized with 1% Na2S2O5, stained 1 min in Ziehl's carbol-fuchsin and decolorized until pink in 35% ethanol containing 0.5% HCI. After 2 min washing, the slide with its adherent water is laid flat on a rack and a volume of 1% Bowie's Biebrich scarlet-ethyl violet stain estimated equal to that of the water on the slide is added. After 5-10 sec, the slide is placed in distilled water and allowed to stand 1-2 min before washing in running water. When the wash water is clear, the slide is drained and rapidly dehydrated with 2 changes of acetone and one of a 1:1 acetone-xylene mixture. A final clearing in xylene and applying a cover glass with a synthetic resin completes the process. Juxtaglomerular granules stain deep purple against a lavender or light blue-violet background. The method was successful with tissues from cat, dog, gerbil, guinea pig, hamster, monkey, mouse, rabbit, rat, cow, pig, chicken and pigeon. In organs other than kidney, mast cell granules, beta cell granules of pancreas and hypophysis, zymogen granules in gastric mucosa and in pancreas, Paneth cell granules, and secretion granules in the submandibular salivary gland were sharply defined.