Proventricular Glands in Fowl

Abstract

Some researchers have already described the fowl proventriculus. However, we believed there was a need for detailed carbohydrate histochemical investigations on the same glands. Moreover, some researchers had erred about the lamina muscularis mucosae. The results of these investigations are as follows. 1. The proventricular glands consist of both superficial and profound gastric glands. 2. The superficial glands are distributed in the lamina propria mucosae while the profound glands exist in the tela submucosa. 3. The superficial glands are simple, branched tubular glands. The columnar glandular cells are arranged in a simple layer and react strongly to PAS, AB (pH 2.5 and 0.5). These appear to be dark purple when they are stained with PAS-AB (pH 2.5). Some other methods have also been tried. 4. Judging from the data 3), the superficial gastric glands contain neutral, weak and strong acids, sulfuric and acid mucopolysaccharides, sialomucin, and II and III neutral mucus type. 5. Glandular cells in the body and basal portions of the superficial gastric glands contain a large number of fine pepsinogen granules. 6. Judging from the data of 3)-5), we believe that the superficial gastric glands are undifferentiated gastric glands and that they are same kinds of glands that are found in mammals. 7. A large number of profound gastric glands fill the tela submucosa. They are compound tubular glands, and are composed of many glandular alveoli. Their columnar glandular cells are arranged in a simple layer. 8. These glandular cells react moderately to PAS, negatively to AB (pH 2.5 and 0.5) and PAS-AB (pH 2.5). Moreover, we observed some other reactions.(ABSTRACT TRUNCATED AT 250 WORDS)

Histomorphological and Histochemical Studies of the Stomach of the Mallard (Anas platyrhynchos)

“…It indicated the presence of both neutral and acidic mucin, respectively. Such observations were similar to those demonstrated by Pastor et al (1988) and Imai et al (1991) in the propria glandular cells in the ventriculus of chicken and fowls, respectively. The presence of neutral and acid mucin may protect the mucosal surface and forms a resistant mucosal barrier in the ventriculus of the birds (Hamdi et al, 2013).…”

Variant AE2 Anion Exchanger Transcripts Accumulate in Multiple Cell Types in the Chicken Gastric Epithelium

“…Higher power magnification of regions within the profound gland indicates that all of the epithelial cells lining the profound gland accumulate AE2 transcripts (data not shown). This observation suggests that each of the epithelial cells of the gland mediates acid secretion, as had been previously proposed (17). The high level of AE2 expression in the cells lining the ducts that connect the profound glands with the lumen was somewhat surprising since these epithelial cells are morphologically distinct from the epithelial cells of the profound gland (17).…”

“…Examination of the cell type-specific pattern of expression of AE2 transcripts in the proventriculus has revealed that they primarily accumulate within the epithelial cells of the profound gland and, to a lesser extent, within the mucus-secreting cells that line the stomach lumen. Previous studies have suggested that the epithelial cells of the profound gland are functionally equivalent to the parietal cells of the mammalian stomach, secreting acid into the stomach lumen (17). The high level of AE2 expression observed in this acid-secreting cell type suggests that the AE2 gene encodes the basolateral anion exchanger of these cells.…”

“…Unlike the mammalian stomach, which possesses secretory glands that are composed of a simple branched tubular epithelium, the proventriculus contains superficial glands, which line the lumen of the stomach and are composed of a simple branched tubular epithelium, and profound glands, which are located in the mucosal tissue beneath the superficial glands and are composed of a compound tubular epithelium. The superficial glands are primarily involved in the secretion of mucus, while the profound glands secrete both H ϩ and pepsinogen into the stomach lumen (17). Furthermore, in contrast to the mammalian stomach, in which acid secretion is mediated exclusively by the parietal cells of the gastric epithelium, all of the epithelial cells of the profound gland are thought to secrete both H ϩ and pepsinogen (17).…”

“…The superficial glands are primarily involved in the secretion of mucus, while the profound glands secrete both H ϩ and pepsinogen into the stomach lumen (17). Furthermore, in contrast to the mammalian stomach, in which acid secretion is mediated exclusively by the parietal cells of the gastric epithelium, all of the epithelial cells of the profound gland are thought to secrete both H ϩ and pepsinogen (17). In situ hybridization studies have determined the cell types in the proventriculus where the variant AE2 transcripts accumulate.…”