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Protoplasma

, Volume 241, Issue 1–4, pp 83–89 | Cite as

Surface characteristics of isopod digestive gland epithelium studied by SEM

  • Agron Millaku
  • Vladka Lešer
  • Damjana Drobne
  • Matjaz Godec
  • Matjaz Torkar
  • Monika Jenko
  • Marziale Milani
  • Francesco Tatti
Original Article

Abstract

The structure of the digestive gland epithelium of a terrestrial isopod Porcellio scaber has been investigated by conventional scanning electron microscopy (SEM), focused ion beam–scanning electron microscopy (FIB/SEM), and light microscopy in order to provide evidence on morphology of the gland epithelial surface in animals from a stock culture. We investigated the shape of cells, extrusion of lipid droplets, shape and distribution of microvilli, and the presence of bacteria on the cell surface. A total of 22 animals were investigated and we found some variability in the appearance of the gland epithelial surface. Seventeen of the animals had dome-shaped digestive gland “normal” epithelial cells, which were densely and homogeneously covered by microvilli and varying proportions of which extruded lipid droplets. On the surface of microvilli we routinely observed sparsely distributed bacteria of different shapes. Five of the 22 animals had “abnormal” epithelial cells with a significantly altered shape. In three of these animals, the cells were much smaller, partly or completely flat or sometimes pyramid-like. A thick layer of bacteria was detected on the microvillous border, and in places, the shape and size of microvilli were altered. In two animals, hypertrophic cells containing large vacuoles were observed indicating a characteristic intracellular infection. The potential of SEM in morphological investigations of epithelial surfaces is discussed.

Keywords

Scanning electron microscopy Focused ion beam Digestive gland epithelium Hepatopancreas Isopoda Crustacea 

Notes

Acknowledgments

We thank FEI Italy for the access to Strata DB235 M at the University of Modena e Reggio Emilia, Italy. This work was supported by the Slovenian Ministry of Higher Education, Science, and Technology (J1-9475). We thank Bill Milne for English editing.

Conflicts of interest

The authors declare that they have no conflict of interest.

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Copyright information

© Springer-Verlag 2010

Authors and Affiliations

  • Agron Millaku
    • 1
  • Vladka Lešer
    • 2
  • Damjana Drobne
    • 2
  • Matjaz Godec
    • 1
  • Matjaz Torkar
    • 1
  • Monika Jenko
    • 1
  • Marziale Milani
    • 3
  • Francesco Tatti
    • 4
  1. 1.Institute of Metals and TechnologyLjubljanaSlovenia
  2. 2.Biotechnical Faculty, Department of BiologyUniversity of LjubljanaLjubljanaSlovenia
  3. 3.Materials Science Department and Laboratory FIB/SEM “Bombay”University of Milano-BicoccaMilanItaly
  4. 4.FEI ItaliaMilanItaly

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