Summary
Fenestrations of the basal lamina of rat intestinal villi were revealed by scanning electron microscopy after removal of the overlying epithelial cells by osmic acid maceration. These fenestrations are circular to oval in shape and are 0.5 μm to 5 μm in diameter. They are richly distributed at a density of 1–2x104/mm2 in the upper two thirds of the villi, except at the very tips. Roughly 500 fenestrations are found on each side of an average sized tongue-shaped villus.
Transmission electron-microscopic observations showed that these fenestrations were passages for migrating cells of the immune system such as lymphocytes, eosinophils and macrophages. Protrusions from the basal parts of epithelial cells were also observed passing through these fenestrations. These findings are discussed with respect to their immunological implications and to the passage of nutrients.
Similar content being viewed by others
References
Bienenstock J, Befus D, Braciale T, McDermott M, Rosenthal K, Tagliabue A (1983) Some aspects of mucosal effector cells. In: Buffalo PLO, Buffalo DMJ (ed) Regulation of the immune response. Karger, Basel, pp 99–106
Collan Y (1972) Characteristics of nonepithelial cells in the epithelium of normal rat ileum. Scand J Gastroenterol 7 Suppl 18:1–66
Creamer B (1974) Intestinal structure in relation to absorption. In: Smith DH (ed) Biomembranes Vol 4A. Intestinal absorption, Plenum Press, London, New York pp 42
Darlington D, Rogers AW (1966) Epithelial lymphocytes in the small intestine of the mouse. J Anat 100:813–830
Desaki J, Fujiwara T, Komuro T (1984) A cellular reticulum of fibroblast-like cells in the rat intestine: scanning and transmission electron microscopy. Arch Histol Jpn 47:179–186
Donnellan WL (1965) The structure of the colonie mucosa. Gastroenterology 49:496–514
Ferguson A (1977) Intraepithelial lymphocytes of the small intestine. Gut 18:921–937
Fichtelius KE (1968) The gut epithelium — a first level lymphoid organ? Exp Cell Res 49:87–104
Guy-Grand D, Vassalli P (1983) Gut mucosal lymphocyte subpopulations and mast cells. In: Buffalo PLO, Buffalo DMJ (ed) Regulation of the immune response. Karger, Basel, pp 122–130
Komuro T, Desaki J, Fujiwara T (1982) Re-evaluation of the fibroblasts and/or fibroblast-like cells. Acta Anat Nippon 57:332–333
Low FN, McClugage SG (1984) Microdissection by ultrasonication: Scanning electron microscopy of the epithelial basal lamina of the alimentary canal in the rat. Am J Anat 169:137–147
Marsh MN (1975) Studies of intestinal lymphoid tissue. Gut 16:665–682
Marsh MN, Trier JS (1974) Morphology and cell proliferation of subepithelial fibroblasts in adult mouse jejunum. Gastroenterology 67:622–635
Mathan M, Hermos JA, Trier JS (1972) Structural features of the epithelio-mesenchymal interface of rat duodenal mucosa during development. J Cell Biol 52:577–588
Meader RD, Landers DF (1967) Electron and light microscopic observations on relationships between lymphocytes and intestinal epithelium. Am J Anat 121:763–774
Naguro T, Takeuchi J, Iino A (1984) SEM observation of the basement membrane through the epithelial side. Acta Anat Nippon 59:686
Otto HF (1973) The interepithelial lymphocytes of the intestinum. Morphological observations and immunologic aspects of intestinal enteropathy. Curr Top Pathol 57:81–121
Partridge BT, Simpson LO (1981) Basal processes on duodenal epithelial cells of man, mouse and rat. Pathology 13:463–472
Rodewald R (1970) Selective antibody transport in the proximal small intestine of the neonatal rat. J Cell Biol 45:635–640
Rodewald R (1973) Intestinal transport of antibodies in the newborn rat. J Cell Biol 58:189–211
Rodewald R (1980) Distribution of immunoglobulin G receptors in the small intestine of the young rat. J Cell Biol 85:18–32
Röpke C, Everett NB (1976) Kinetics of intraepithelial lymphocytes in the small intestine of thymus-deprived mice and antigen-deprived mice. Anat Rec 185:101–108
Rubin W (1971) The epithelial “membrane” of the small intestine. Am J Clin Nutr 24:45–64
Simpson LO (1980) Basement membranes and biological thixotropy: a new hypothesis. Pathology 12:377–389
Toner PG, Ferguson A (1971) Intraepithelial cells in the human intestinal mucosa. J Ultrastruct Res 34:329–344
Toner PG, Carr KE, Wyburn GM (1971) The digestive system: An ultrastructural atlas and review. In: Excerpta Medica Int. Cong. Ser 391 Butterworths, London pp
Trier JS (1968) Morphology of the epithelium of the small intestine. In: Code CF (ed) Handbook of physiology, section 6. Alimenary canal, Vol. 3. Intestinal absorption, Am Physiol Soc, Washington DC
Trier JS, Rubin CE (1965) Electron microscopy of the small intestine: a review. Gastroenterology 49:574–603
Warfel KA, Hull MT (1984) Migration of lymphocytes through the cutaneous basal lamina in normal skin: an ultrastructural study. Anat Rec 208:349–355
Warshaw AL, Walker WA, Isselbacher KJ (1974) Protein uptake by the intestine: evidence for absorption of intact macromolecules. Gastroenterology 66:987–992
Williams EW, Hemmings WA (1978) Intestinal uptake and transport of proteins in the adult rat. Proc R Soc Lond B 203:177–189
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Komuro, T. Fenestrations of the basal lamina of intestinal villi of the rat. Cell Tissue Res. 239, 183–188 (1985). https://doi.org/10.1007/BF00214918
Accepted:
Issue Date:
DOI: https://doi.org/10.1007/BF00214918