George G. Glenner

THE HISTOCHEMICAL DEMONSTRATION OF INDOLE DERIVATIVES BY THE ROSINDOLE REACTION OF E. FISCHER

1. The application of the rosindole reaction of E. Fischer to the histochemical localization of indole derivatives is described. This method demonstrates predominantly the tryptophan moiety of proteins and it therefore depends on the degree of protein fixation produced by formaldehyde. 2. The specificity of the rosindole reaction is established and the comparison is made between it and both the xanthydrol and post-coupled benzylidene reactions. 3. The facility of the histochemical technique as well as its specificity, sensitivity, and sharp localizability recommends the use of the rosindole reaction in routine histopathological investigation.

HISTOCHEMICAL DEMONSTRATION OF A PATHWAY FOR POLYSACCHARIDE SYNTHESIS FROM URIDINEDIPHOSPHOGLUCOSE

ehunonides svnul hcshzcd hsisi ochensictolly frolns glum(use1 -pbuophnul e (( -1-F) ui-si mug pninser, nodemuylic F’ton. 1. Beta glucumronidasc activity in rat liver by 8-hydroxy-quinsolin-glutcutronuide tcchnsique. Tuventyfounr houmr fixation in chloral hydrate formahinu. Note diffuse cytopluosmic activity amiol marked locahizaItous uns bile cuopillary is-all-s nond penicanunohicoilnor cytoplasm.

FURTHER OBSERVATIONS ON HISTOCHEMICAL ESTERASE AND AMIDASE ACTIVITIES WITH SIMILARITIES TO TRYPSIN

When the histochemical substrates benzoyl-dl-arginine β-naphthylamide, benzoyl-dl-lysine β-naphthylamide, Naphthol AS and AS-D ε-aminocaproate, and Naphthol AS β-alanyl glycinate were tested with tissue sections and as substrates for purified enzymes, a species-limited enzyme activity having substrate specificity and enzymic kinetic and affector characteristics strikingly similar to those of bovine trypsin was noted in human mast cells. The ester substrates were hydrolyzed in several other tissue sites, and, in those tested, hydrolysis appeared to be related to the activity of an aliesterase(s) with substrate specificity and affector characteristics markedly different from those of bovine trypsin. Although Naphthol AS chloroacetate has been defined as a substrate for a chymotrypsin-like enzyme in rat mast cells, the definite possibility exists that its hydrolysis in human mast cells in fresh frozen tissue sections may be due at least its part to the activity of a trypsin-like enzyme.

Tetrazolium reduction as a measure of monoamine oxidase activity in vitro.

1 . Data has been presented showing that tetrazolium salts can be used for the histochemical localization of monoamine oxidase, although there are limitations to its application to in vitro studies. These limitations have been discussed. 2. It appears that an indole carbonyl compound is necessary for 2-(p-iodophenyl)-3-(p-nitrophenyl)-5-phenyl tetrazolium chloride reduction. A diaphorasetype system may be required to transfer the electrons from the indole carbonyl intermediate to INT.

THE HISTOCHEMICAL DEMONSTRATION OF ENZYMATIC ACTIVITY BY A NONENZYMATIC REDOX REACTION. REDUCTION OF TETRAZOLIUM SALTS BY INDOLYL-3-ACETALDEHYDE

The availability of synthetic indolyl-3-acetaldehyde has made possible the determination of the mechanism of reduction of tetrazolium salts in the tryptamine-tetrazolium technique for the demonstration of monoamine oxidase activity. This aldehyde, formed as the result of the enzymatically catalyzed oxidative deamination of tryptamine, directly reduces sensitive tetrazolium salts to localize monoamine oxidase activity in tissue sections. No implication of a diaphorase-like system in the reduction of the tetrazoles was found. The possibility of a pigment precursor being formed as the result of the oxidation of the indolyl aldehyde during tetrazole reduction is discussed and the utilization of a similar scheme of nonenzymatic reduction of an indicator dye for demonstrating both oxidative and hydroytic enzyme systems is presented.

On the experimental discharge of the gastric and intestinal argentaffin cells.

Reserpine discharges the azo positive reducing substance from both gastric and intestinal basal granular cells in the guinea pig. Regeneration was slower than in previous reports and apparently more rapid in the duodenum than in the stomach or ileum. The numbers of cells demonstrated in the normal duodenum and ileum respectively, as well as in the duodenum and ileum of the 7 day post reserpine animal, do not correspond particularly closely with the 5-hydroxytryptamine assays. Physostigmine and ephedrine failed to discharge the reactive material from basal granular cells of the guinea pig stomach and intestine. Argyrophil cells persist throughout the reserpine discharge period, during which argentaffin, azo positive basal granular cells are not demonstrable.

SUBSCRIBER SURVEY OF THE JOURNAL OF HISTOCHEMISTRY AND CYTOCHEMISTRY 1972

In January 1972, a survey of our subscribers was initiated by the Editor, a publications committee of editorial board members and the staff of the publisher. A questionnaire, designed to elicit information about the reader’s professional background. scientific interests, reading habits and publication preferences, was mailed to 407 individual subscribers on January 25, 1972. A cut-off date of March 24, 1973, was stipulated. The response rate was 58.7% and the data were tabulated and analyzed by the Market Research Department of the Williams & Wilkins Company. From this analysis, the following highlights emerged. The majority of subscribers (77(7) are between 35 and 59 years of age (mean = 46.2 years) and they have either a Ph.D. or M.D. degree. They are engaged in a remarkable variety of biomedical specialties including (in order of frequency) pathology, biology, histochemistry, anatomy, cytochemistry. cytology, histology, biochemistry, research medicine, neurochemistry, physiology, oncology, electron microscopy, immunology, microbiology, endocrinology, pharmacology, hematology, chemistry, dermatology, zoology, botany, biophysics, psychiatry, neuropathology, renal disease, cardiology, enzymology, neurology, urology, plant physiology, pulmonary disease, entomology, engineering, ecology, nuclear medicine and surgery. The leading primary field of professional activity is pathology (30%) and the subscribers devote most of their time to research and teaching. The subscriber scans everv issue of the JOURNAL, reads about half of the articles and rates the JOURNAL as very good to excellent in its presentation of contributions to the development, evaluation and application of histochemical and cytochemical methods. Subscribers also mentioned 43 other journals that are regularly read but the most frequently cited were the Journal of Cell Biology, Histochemie and the Histochemical Journal. Almost all subscribers have had articles published. When asked about the primary reasons for submitting their manuscripts to a particular journal, the following were the most important: (a) the appropriateness of the author’s material for the journal chosen, (b) the reputation and prestige of the journal, (c) the wide circulation of the journal. (d) the quality and fairness of the manuscript review by the editorial borad, (e) the quality of typography and reproduction of illustrations and (1) the promptness of publication after submission of the manuscript. Page charges and limitations on manuscript length did not seem to be significant factors in the selection of journals for publication. A request to list subjects areas or topics that should receive more emphasis in the JOURNAL resulted in 241 suggestions. The topics that interested most suhscribems fell into two major groups: methods and applica-

Pepsin release of guinea pig enterochromaffin substance.

I)uning histochemictul expenimenuts on enzym utic digestiomi of tissuie sections, it n-as foumnd t hat pepsin i ticuibat iou’s nemovetl t he enterochroniaffinu suibstausce from formtult!ehvt!e fixed guiinetu pig duiodenttun anst! gtustnic fuinut!uis. The enterochromaffin suibstatuce is only mtuititained adequiatehy its tissuse pneviouislv treatet! with a fornnabdehuyt!e fixnutive. Siuuce localiztutiolu of the eritenochromsitiffin sumbsttihuce to small granuibcs n-ithius the emsterochromtuffins cells is excellent,