Staining Juxtaglomerular Granules with Basic Fluorescent Stains

Many basic fluorescent dyes stain juxtaglomerular granules to produce characteristic colors in ultraviolet light. The stain is applied to paraffin sections of tissues fixed in 2% calcium acetate-10% formalin or in phosphate-buffered 10% formalin. Procedure: Bring section to water, stain 0.5 min in Delafield hematoxylin, wash in tap water, stain 3 min in a 0.1% aqueous solution of basic fluorescent dye (auramine O, acriflavine, acridine orange, coriphosphine O, acridine yellow, phosphine E, thioflavine T, berberine sulfate, atebrine or rivanol) and differentiate 1 min in 0.1% acetate acid (or omit this step). After washing in tap water, air dry with or without subsequent mounting in a resin. Juxtaglomerular granules stain bright fluorescent yellow or orange against a dark background.