Histoplanimetrical Study on the Spatial Relationship of Distribution of Indigenous Bacteria with Mucosal Lymphatic Follicles in Alimentary Tract of Rat

Abstract

ABSTRACT. The spatial relationship between the distribution of indigenous bacteria (IB) and the situation of mucosal lymphatic follicles (LF) is histoplanimetrically studied in the rat alimentary tract. From the oral cavity to the nonglandular part of the stomach, IB adhered to the corneal layer of the most luminal mucosa. In the glandular part of the stomach, IB adhered only to the most luminal mucosa but not in the gastric pits. In the small intestine, IB consistently adhered around the apices of both intestinal villi and the domes, and their amounts decreased toward their basal portions. No IB entered the intestinal crypts. In the large intestine, IB consistently adhered to the most luminal mucosa. Numerous IB were suspended in the intestinal crypts of both the cecum and the proximal colon, whereas there were no IB in the crypts of the distal colon and the rectum. When IB spread over the basal portions of the intestinal villi, IB with the same morphology were detected on the neighboring LF, whereas no bacteria were detected on the neighboring LF, when IB were located in the apical to middle portions of the intestinal villi. This close relationship between the distribution of IB and mucosal LF was also observed in the large intestine. These results suggest that the most luminal mucosae are a fundamental settlement site of IB throughout the alimentary tract and that the hyperproliferation of IB's colonies might be detected by neighboring LF in the rat intestine.

Immunohistochemical and Histoplanimetrical Study on the Spatial Relationship between the Settlement of Indigenous Bacteria and the Secretion of Bactericidal Peptides in Rat Alimentary Tract

“…Our previous study clarified that lysozyme and sPLA2 are secreted from Paneth cells in the rat small intestine [29]. In the present study, lysozyme and sPLA2 in secretory granules of Paneth cells are most frequently and strongly expressed in the ileum, previously suggested as the most frequent residence site of indigenous bacteria in the rat small intestine [27]. In this study, the lysozyme-and sPLA2-positive secretory granules decreased, but negative or weakly positive vacuoles increased in the Paneth cells of the intestinal crypts in the sites where indigenous bacteria proliferate into the deep intervillous spaces.…”

“…In the small intestine, bacilli or cocci mainly colonize on the epithelia of the villous apices. From the cecum to the ascending colon, a large amount of indigenous bacteria mainly consisting of bacilli reside in the intestinal crypts, whereas the indigenous bacteria reside only in the most luminal mucosa in the distal colon and the rectum [27]. In the large intestine, Gram-positive lactobacilli, Gramnegative bacteroides and E. coli are defined to be predominant by a microbiological technique [17].…”

“…In rats, the fundamental settlement sites of indigenous bacteria have been determined to be the most luminal sites of the mucosae throughout the alimentary tract [27]. Several possible sugars that are specific for indigenous bacterial lectins, are expressed restrictedly on the lateapoptotic epithelial cells of the most luminal sites of mucosa in the rat jejuno-ileum [3] and through the rat alimentary tract [28].…”

Histoplanimetrical Study on the Relationship between Cellular Kinetics of Epithelial Cells and Proliferation of Indigenous Bacteria in the Rat Colon

“…A similar process is believed to occur in the large intestine [10,15,41,42]. On the other hand, the fundamental settlement sites of indigenous bacteria are the apices of both the intestinal villi and domes of mucosal lymphatic follicles in the rat small intestine [11,22,23,44], and around the crypt orifices of the most luminal mucosa in the rat large intestine [44]. At these sites, apoptotic epithelial cells are incessantly shed into the intestinal lumen.…”

A Pharm-Ecological Perspective of Terrestrial and Aquatic Plant-Herbivore Interactions

“…Nonetheless, there are other examples in domestic ruminants (Majak, 1992) where an increase in toxicity occurs via microbial modification. Although hindgut fermenters are expected to benefit from microbial detoxification of PSMs less than foregut fermenters, microbes inhabit the mucosal lining of the intestine prior to the cecum in many terrestrial (Frey et al, 2010;Yamamoto et al, 2009) and aquatic animals (Ganguly and Prasad, 2011;Mondal et al, 2008). Additional studies are clearly needed to identify the positive and negative influences microbial communities have on herbivores with either complex or simplified digestive tracts such as those found in marine and freshwater invertebrates (Brunet et al, 1994;Freese and Schink, 2011).…”