OBSERVATIONS ON NAPHTHOL STAINING AND THE HISTOCHEMICAL LOCALIZATION OF ENZYMES BY NAPHTHOL-AZO DYE TECHNIQUEDEFENDI, V.
doi: 10.1177/5.1.1pmid: 13416562
A group of naphthols—1- and 2-naphthol, 6-benzoyl-2-naphthol and 6-bromo-2-naphthol—have been investigated in relation to their tissue affinity. It has been found that naphthol binding is mainly dependent on the solubility of the naphthols and on the type of tissue considered. Time of incubation, naphthol concentration and pH also play in important role in the intensity of the resulting stain. 1- and 2-naphthol have very little affinity for cell constituents, while 6-bromo-2-naphthol and 6-benzoyl-2-naphthol are strongly bound by cellular structures. The affinity of the latter two naphthols is specific for cell parts and tissue type: the cytoplasm of epithelial cells is strongly stained, while connective tissue, kidney glomeruli and inner medulla and cell nuclei at the concentration used devoid of any naphthol binding.Correlated experiments have been carried on the histochemical demonstration of enzymes utilizing the esters of these naphthols, by simultaneous and post-incubation coupling methods. Considerations have been offered on the importance of specific tissue and cellular affinity of insoluble naphthols in relation to the reliability of histochemical localization of enzymes by the post-incubation coupling technique.
THE STAINING OF COLLAGEN WITH ELASTIC TISSUE STAINSFULLMER, HAROLD M.; LILLIE, R. D.
doi: 10.1177/5.1.11pmid: 13416563
We have demonstrated that acetylation or benzoylation of formalin-fixed collagen from the human, rat, or mouse induces its reactivity with the elastic tissue stains: orcein, Weigert's resorcin fuchsin, orcinol-new fuchsin, and Verhoeff's, and blocks the Masson trichrome and the Van Gieson stains which are used to identify collagen. Deamination of collagen induces its reactivity with Gomori's aldehyde fuchsin perhaps because of a net shift of the reaction of collagen to the acid side.
THE DIFFERENCE IN PERMEABILITY OF CARTILAGE TO CATIONIC AND ANIONIC DYESKANTOR, THOMAS G.; SCHUBERT, MANWELL
doi: 10.1177/5.1.28pmid: 13416565
It has been shown that fresh cartilage cubes are readily permeable to all of thirteen cationic dyes and one neutral dye tried. They are impermeable to thirteen of fourteen anionic dyes tried. This selective permeability of fresh cartilage to dyes can be altered by treatment which destroys the fixed negative charge of the cartilage. After this treatment, the cartilage cubes are readily permeable to anionic dyes.It is suggested that this membrane selectivity of cartilage may have physiological meaning.
THE ALKALINE PHOSPHOMONOESTERASE ACTIVITY OF CELL NUCLEI: ACTIVATION BY 0.16M MAGNESIUMFEIGIN, IRWIN; WOLF, ABNER
doi: 10.1177/5.1.53pmid: 13416568
I. The presence of 0.16M magnesium chloride in the incubation mixture for the Gomori method for localizing alkaline phosphatase activity, markedly increases the enzyme activity in the nuclei of the guinea pig endometrium, ovary and adrenal cortex, rendering them visible after 5 minutes' incubation. The activity in cytoplasmic and extracellular sites is decreased. The staining of these same nuclei could be demonstrated by the Loveless and Danielli method of visualizing the phenolic component of a complex phosphate ester instead of precipitating the phosphate ions with calcium salts. The activity described may be specific for the tissues mentioned and serves as an instance in which nuclear staining in phosphatase preparations is clearly valid.II. The effect of magnesium and cyanide ions and other factors on the enzyme activity noted histochemically in nuclei and biochemically in nuclear cell fractions, was reviewed. The data support the validity of some earlier histochemical observations describing a nuclear phosphomonoesterase activity in many organs which differs from that in cytoplasmic and extracellular sites. They also suggest that the phosphatase activity in cell fractions of those biochemical preparations prepared in aqueous media are altered by diffusion and adsorption phenomena.
A COMPARISON BETWEEN THE HISTOCHEMICAL DEMONSTRATION OF NON-SPECIFIC ESTERASE ACTIVITY BY 5-BROMOINDOXYL ACETATE, α-NAPHTHYL ACETATE AND NAPHTHOL AS ACETATEPEARSON, BJARNE; DEFENDI, VITTORIO
doi: 10.1177/5.1.72pmid: 13416570
5-Bromoindoxyl acetate was used as a substrate for the histochemical demonstration of esterases.The pH optimum for this salt as used in this study was approximately 5. This differed from the optimum when α-naphthyl and naphthol AS acetates were used, which showed an optimum as determined by color reaction of between 7.3 and 8.4. This latter may be an artifact due to non-enzymatic hydrolysis. Naphthol binding may also vitiate the results. If these hydrolytic artifacts could be eliminated, the true optimum may be of a lower order.No hydrolysis or diffusion artifacts occur in any pH range with the 5-bromoindoxyl acetate. This may occur with the unsubstituted indoxyl acetate.The esterase reactions in various tissues following the use of 5-bromoindoxyl acetate was similar to the α-naphthyl and naphthol AS acetates with the exception of the large intestine which was negative with the 5-bromoindoxyl acetate.The reaction with 5-bromoindoxyl acetate was enhanced by taurocholate in the pancreas and inhibited in the kidney, liver and intestine. This seems to indicate that 5-bromoindoxyl acetate is hydrolyzed by both lipases and esterases from the data of this study.Because of the fine and uniform granularity of the resulting 5,5' dibromoindigo crystals, this substrate should be valuable in the study of esterases.