To find the differences among mammals in Club cells Plopper and colleagues performed three research studies to quantitatively and qualitative assess Club cells among mammals used in lung research [1-4]. In the first study researchers examined lung tissue from adult male rabbits, guinea pigs, rats and hamsters. Lung tissue from four male rabbits, four male guinea pigs, six male rats and eight male hamsters was used. Each animal was sedated with pentobarbital, had trachea cannulated, and thoracic contents removed all together. Before processing lung tissues by a selective embedding technique, airways were fixated by airway infusion at constant pressure and bronchioles were examined by electron microscopy [1]. The lungs were fixed by airway infusion of paraformaldehyde and glutaraldehyde in a cacodylate buffer. Parts of fixed left lower lobes were post-fixed for 2 hours in 1% osmium tetroxide. The blocks of lung tissues were embedded by processes, which allow selection of specific areas from large tissue in either a mixture of Epon 812 and Araldite 6005 or Araldite 502 resin alone. One-micron (1μm) thick sections were produced with glass blades on Sorvall JB4. Thin sections of about 300 to 500 Ångström (Å) were produced with diamond knives on a Sorvall MT2 ultramicrotome. The thin sections were then stained with uranyl acetate and lead citrate, followed up with an examination with a Philips 300 electron microscope (EM) at 80-kilovoltage (KV) [1]. The difference in granules and assessment of organelles was addressed as follows. First, only the most distal non-alveolarized bronchioles were lined because of the direct continuation into one or more alveolar ducts [1]. Club cells were evaluated only if the plane of section passed throu...
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...an with comparison of 15 mammalian species. Experimental Lung Research;1(2):171-80
4 Plopper, CG., Mariassy, AT., Wilson, JL., Alley, SJ., Nishio, SJ., Nettesheim, P. (1983).Comparison of nonciliated tracheal epithelial cells in six mammalian species: ultrastructure and population densities. Experimental Lung Research; 5: 281-294
5 Cortese, K., Diaspro, A., & Tacchetti, C. (2009). Advanced correlative light/electron microscopy: Current methods and new developments using tokuyasu cryosections. Journal of Histochemistry & Cytochemistry, 57(12), 1103-1112.
6 Sjollema, K. A., Schnell, U., Kulpers, J., Kalicharan, R., & Giepmans, B. N. (2012). Correlated light microscopy and electron microscopy. Methods in Cell Biology, 111, 157-73.
7 Harvard Medical School .How is EM different from light microscopy?. (2014, March 24). Retrieved from http://bsp.med.harvard.edu/node/222