SIRIUS RED AND ACID FUCHSIN STAINING MECHANISMS

The purpose of the study was to investigate the staining mechanism of acid fuchsin and Sirius red, Acid (poly-glutamic acid), neutral (poly- hydroxyproline) and basic (poly-arginine, poly-histidine, poly-lysine) poly-amino acids, collagen types I, II and III, and arginine-and lysi ne-containing histones were used as test substances applied to nitroce llulose membranes as dot blots, Five micrometer sections of granulatio n tissue on slides were tested in parallel, Some dots and sections wer e treated with chloramine-T before staining with acid fuchsin and Siri us red and some with 1 M NaOH after staining, The acid and neutral pol y-amino acids were not stained, but the basic amino acids polylysine a nd poly-arginine, poly-amino acids containing these basic amino acids and the histones and the collagens exhibited intense staining, Oxidati ve deamination by chloramine-T abolished the staining and P M NaOH rem oved the staining except in the case of poly-arginine, Tissue sections treated in the same way showed a considerable decrease in staining af ter oxidative deamination with chloramine-T; in particular, tbe staini ng of the smaller fibers was abolished. The staining was totally remov ed by destaining with 1 M MaOH.