Rivista di istochimica, normale e patologica最新文献

By means of the technique proposed by De Robertis and Grasso (1946) for the histochemical localization of peroxidase activity, we have shown in the developing chicken Bursa of Fabricius positive cells from the 12th day onwards. They are localized in the mesenchymal network and increase during the development, reaching their top level in a period between the 18th-20th day before hatching and the 3rd day after hatching. After the first week these cells decrease and disappear during the second month. Peroxidase positive cells are tentatively identified as eosinophilic granulocytes (pseudoeosinophilic according to Romanoff); their variations should express fluctuations in the pattern of bursal granulocytopoiesis.

The AA. describe an endocrine cells presence in the Pig Brunner's duodenal glands by means of histochemical methods at light microscope. Between these they can recognize two types of cells: these enterochromaffins (EC) and these non-enterochromaffins (non-EC), both presents either in the secretory part of the glands or in the deeper parts of the ducts. The EC-cells show generally a prismatic size and their apical part attains the glandular cavity. Their granules are much numerous and recognizables either in the basal part or in other parts of the cells. The non-EC-cells show a variable, from the prismatic to the spheroidal, size. Their granules are numerous and recognizables mostly in the basal part of the cells. Between the non-EC-cells they can also differentiate at least three types: a) these Davenport-positives and poorly argyrophils; b) these Davenport-positives and clearly argyrophils and c) these Davenport-negatives and clearly argyrophils. All cells are by lead-haematoxylin stainables, while by the HCL-BT method the EC-cells are ortochromatics and these non-EC are metachromatics.

Using histological and histochemical methods for the identification of biogenic amins, phenolic and indolic groups, and of substances with a proteine and carbohydrate nature, it has been possible to identify at least five types of endocrine cells in the gastric mucose of Scyliorhinus stellaris and Scyliorhinus canicula. One of these, a type I cell, localised mainly in the piloric portion, shows morphological and histochemical characteristics which are perfectly comparable with those of the enterochromaffin type found in the gastro-intestinal tract of mammals. On the other hand, the four remaining cellular types are more difficult to define; three of these latter are present solely in the pyloric mucose, i.e., (a) type II cells with slightly fluorescent and metachromatic granules, with a positive reaction to the Grimelius test and to proteine test, and completely negative and argentaffin methods, (b) type III cells with non-fluorescent granules, but metachromatic and postive to argentaffin methods, and (c) type IV cells with slightly (argyrophilic) granules, strongly metachromatic and positive to the PAS test and to the tryptophan test, respectively. Types II and IV have been hypothetically correlated with the G and D cells, respectively, of mammals. The fifth cellular type, present solely in the central portion of the stomach has exclusively argyrophilic granules. This latter cellular type is considered similar to the ECL type, mammalian cell. No hypothesis, however, has yet been ventured with respect to the cells belonging to the third group.

Based on morphological and histochemical data, the Authors describe the distribution of "EC" (5-HT-producing) and of the other endocrine cells of the "APUD" series (polypeptide hormone-producing) in the gastro intestinal tract of weaned and unweaned 3-4 month old calves. The results demonstrate that: -- no difference concerning the different diet can be correlated; -- no endocrine cell is present in the vorestomachs; -- the "EC" cells in the abomasum prevail in the fundus glands; they are demonstrable also in every tract of the intestine and are more numerous in the duodenum and in the rectum; -- within the "APUD" series four cellular types are demonstrable in the abomasum; two are in the cardias, one in the fundus and one in the pylorus glands; the last one probably corresponds to the gastrin-producing "G" cells. -- In the small intestine, particularly numerous in the duodenum, a probably heterogeneous family of endocrine cells is present, while in the coecum, in the colon and, above all, in the rectum, cells probably corresponding to "EG" cells are identifiable. These results are compared to those previously obtained in the adult Cattle: remarkable differences are demonstrable only within "APUD" cells of abomasum.