title: Immunohistochemical and histoplanimetrical study on the spatial relationship between the settlement of indigenous bacteria and the secretion of bactericidal peptides in rat alimentary tract.
abstract: To clarify the regulatory mechanism by bactericidal peptides secretion, the secretion of bactericidal peptides was immunohistochemically and histoplanimetrically compared with the degree of Gram-positive/negative bacterial colonization throughout the rat alimentary tract. In the associated exocrine glands from the oral cavity to the stomach, no comparable differences were observed under the changes of development of indigenous bacterial colonies. In the small intestine, immunopositive granules for lysozyme and secretory phospholipase A2 (sPLA2) were markedly decreased, whereas immunopositive vacuoles in the Paneth cells were more increased at sites with hyper-development of indigenous bacterial colonies in the intervillous spaces than at sites with no or less development. No changes in exocrine glands were observed in the large intestine because of the constant existence of large quantities of bacteria. Gram-positive bacterial colonies on the mucosal surfaces were dominant from the oral cavity to the stomach. Gram-negative bacteria were dominant in the large intestine, and the distributions of both Gram-positive and negative bacteria were intermediate in the small intestine. These findings suggest that lysozyme and sPLA2 secreted from the Paneth cells contribute to the regulation of the proliferation of indigenous bacteria in the intervillous spaces of the small intestine, and that the inversion of distributions of Gram-positive and -negative bacteria in the alimentary tract might be caused by the secretion of lysozyme and sPLA2 in the small intestine.
authors.affiliation: Department of Bioresource Science, Graduate School of Agricultural Science, Kobe University, Kobe 657–8501, Japan.
authors.forename: Yuh
authors.initials: Y
authors.lastname: Yokoo
authors.forename: Hidenori
authors.initials: H
authors.lastname: Miyata
authors.forename: Kankanam Gamage Sanath
authors.initials: KG
authors.lastname: Udayanga
authors.forename: Wang-Mei
authors.initials: WM
authors.lastname: Qi
authors.forename: Ei-Ichirou
authors.initials: E
authors.lastname: Takahara
authors.forename: Youhei
authors.initials: Y
authors.lastname: Mantani
authors.forename: Toshifumi
authors.initials: T
authors.lastname: Yokoyama
authors.forename: Junichi
authors.initials: J
authors.lastname: Kawano
authors.forename: Nobuhiko
authors.initials: N
authors.lastname: Hoshi
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Kitagawa
mesh_terms: D000818:Animals; D004947:Esophagus / Q000378:metabolism / Q000382:microbiology; D005088:Exocrine Glands / Q000201:enzymology / Q000378:metabolism*; D005753:Gastric Mucosa / Q000378:metabolism / Q000382:microbiology; D041981:Gastrointestinal Tract / Q000378:metabolism / Q000382:microbiology*; D006090:Gram-Negative Bacteria / Q000254:growth & development*; D006094:Gram-Positive Bacteria / Q000254:growth & development*; D007150:Immunohistochemistry; D007413:Intestinal Mucosa / Q000378:metabolism / Q000382:microbiology; D007420:Intestine, Large / Q000378:metabolism / Q000382:microbiology; D007421:Intestine, Small / Q000378:metabolism / Q000382:microbiology; D008297:Male; D009113:Muramidase / Q000378:metabolism*; D019879:Paneth Cells / Q000378:metabolism; D054497:Phospholipases A2, Secretory / Q000378:metabolism*; D051381:Rats; D017208:Rats, Wistar; D013270:Stomach / Q000382:microbiology; D014059:Tongue / Q000378:metabolism / Q000382:microbiology; D023083:beta-Defensins / Q000378:metabolism*
chemical_list: D023083:beta-Defensins; D054497:Phospholipases A2, Secretory; D009113:Muramidase