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A Contribution to the Biology of the Epidermis: Stratum Oxybioticum

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A Contribution to the Biology of the Epidermis: Stratum Oxybioticum View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector A CONTRIBUTION TO THE BIOLOGY OF THE EPIDERMIS: STRATUM OXYBIOTIGUM AND STRA TUM ANOXYBIOTIGUM* J. FERREIRA-MARQUES, M.D. In this short report a study of the granularof cells or 2 or 3 rows) the granular cell appeared layer is presented and a new concept on thein perpendicular sections cut in all directions of biology of the epidermis is introduced. the compass as the profile of a bieonvex lens whose plasticity apparently permitted stretching METHOD AND MATERrAL5 of all the borders, thus forming a thin eyto- Biopsy specimens of the skin were fixed inplasmie plate in the shape of a flat ring around 8% formalin solution with 1% nickel nitratethe central nuclear region. In profile it had a added for 1 to 3 days. The addition of nickelpropeller-like shape. In horizontal cuts, from nitrate assures better fixation, especially ofabove, it looked like a straw hat with a convex nuclei and of elastic tissue. Orth's fixative wascrown and flat brim which evidently adapted used, substituting the sodium sulfate with nickelitself under the horny layer to its environment, nitrate. Fixations were also done with 20% pureparallel to the surface. In both kinds of speci- formalin solution, with osmie acid and othermens with thin and thick granular layer it always fixatives. appeared as a diaphragm between the Mal- The most frequently used staining methodspighian layer and the stratum lucidum or stratum were H and E, Mallory's, Giemsa's, Van Gieson'seorneum. and Mayer's hemalum. Also used were Regaud's The keratohyalin granules are not uniform and Heidenhain's iron-hematoxylin, Altmann'sin volume, shape, contours or staining properties. fuchsin acid, Pinkus and Steel's technic, JanusThe largest and most intensely stained granules Green B, neutral red, osmium tetroxide andwere found around the nucleus. In general, the silver impregnation. Vital stains were performedarrangement of the granules is geometrically so in self-experiments and on the skin of guinea-regular that they remind one of the representa- pigs and rats. tion of an atomic model, with the nucleus in Biopsy material was taken from palms, dorsathe center and the keratohyalin granules around of hands, scalp, thorax, extremities and scrotum.it like shells of electrons. It looks as if in a continuously moving protoplasm the granules RESULTS have become fixed at a certain point in their Morphological studies of the granular layersorbit like satellites around the nucleus. were done in collaboration with Dr. C. A. Parra. In agreement with the reports of Montagnn We found that the fundamental shape of the(1), Horstmann (2) and others, I found that the cells in this layer is that of a biconvex lens withgranular cells have no Golgi apparatus and the its long axis parallel to the skin surface. Inmitoehondria are diminished and degenerated. specimens in which the granular layer consistedAs Montagna stated "Mitoehondria gradually of many rows of cells, such as specimens fromdisappear from the cells of the upper layers of palms and soles, the granular cell appeared inthe stratum Malpighii". perpendicular cuts as the profile of a bieonvex Using the Feulgen-Sehiff reaction I was able lens of short focal distance. Its upper surfaceto confirm the findings of Leuehtenberger and showed a double socket corresponding with theLund (3) who showed that the nuclei of basal lower edge of the cell above it, the two edgescells and of granular cells have the same DNA being adapted. The granular layer as a wholecontent. reminded one of a stone pavement arrangement. Study of the tonofibrils by Unna's chromation In specimens with thin granular layer (1 rowmethod showed us that in the granular cell the system of tonofibrils is diminished and the *Fromthe Department of Dermatology (Prof. J. Ferreira-Marques, M.D., Chairman), Universi-fibrils are fragmented. But in certain regions, dad Nacional de Cuyo, Facultad de Cienciasparticularly next to the cellular membrane, the Médicas, Mendoza, Argentina. Received for publication December 1, 1959. epidermal fibrils show up well and have a normal 63 64 THE JOURNAL OF iNVESTIGATIVE DERMATOLOGY appearance. The tonofibrils become reducedlayer, stratum lueidum and horny layer is possibly because of partially being transformedanoxybiotic and may be called stratum anoxy- into keratohyalin granules. bioticum. The latter zone's main function is In confirmation of other investigators (4, 5,formation of epidermal keratin ("Keratino- 6, 7) I found large amounts of glycogen in thepoiesis"). upper two-thirds of the Malpighian layer, particularly in epidermal specimens with intense SUMMARY keratogenous activity such as in palms, soles, Study of the granular layer suggests that the hooves, etc. In the granular layer itself, nocells of this layer have an anoxybiotic (fermenta- glycogen is present, or only traces are seen. tive) metabolism. It is concluded that the An important fact, as also pointed out byepidermis can be divided into two zones, each otherinvestigators (6), refers to the position of having a different metabolism. The proximal thegranular layer within the epidermis: it iszone, consisting of basal and prickle cell layers, separated and isolated from the blood capillariesutilizes oxygen and have an oxybiotie metabolism by many cell layers, and thus it seems to be cut ("stratum oxybioticum"). The peripheral zone off from oxygen supply. Oxygen uptake fromconsists of the stratum granulosum, stratum the atmosphere is hindered by the interpositionlucidum and stratum corneum and has a fermen- of the stratum corneum. tative metabolism ("stratum anoxybioticum"). The following facts about granular cells appear to have biological significance: they have no REFERENCES Golgi apparatus, their mitochondria are de- 1. MONTAGNA, WILLIAM: The Structure and generated and their tonofibrils are reduced. The Function of Skin, pags. 33—39, Academic Press Inc. Publishers, New York, 1956. DNA content of the nuclei is not reduced. Due 2. HOR5TMANN, E.: Handbueh der Mikroskopi- to its anatomical position, the granular cell schen Anatomie des Mensehen, 3, III, pags. probably does not have sufficient oxygen supply. 1—54. Springer-Verlag, Berlin, Gottiogen, Heidelberg, 1957. In the underlying cell layers there are substantial 3. LEUdHTENBRRGER, C. AND Luxn, H. Z.: The amountsof glycogen. chemical nature of the called keratohyaline granules of the stratum granulosum of the DI5CU55ION skin. Exper. Cell Res., 2: 150, 1951. 4. BRADFIELn, J. R. G.: Glyeogen of vertebrate Itis well known that the mitoehondria are epidermis. Nature, 167: 40, 1951. 5. MONTAGNA, W., CHASE, H. B. AND HAMILTON, richin enzymes. They can be regarded as J. B.: Distribution of glycogen and lipids in autonomous respiratory structures of the cell human skin. J. Invest. Dermat., 17: 147, (5—12). Absence of mitochondria and absence of 1951. 6. Dura4, ANDR4: Contribution al'EtudeHisto- oxygen in the granular cells indicate that their ehimique des Glucides de la Peau Humaine, metabolismis anoxybiotic or fermentative. It is These, Toulouse, 1952. possible that the cells of the granular layer 7.BRAUN-FALcO,0.: Histoehemisehe und mor- phologische Studien an normaler und patho- utilizethe glycogen from the layer below it by logiseh veritnderter Haut. Arch. f. Dermat. wayof anaerobic glycogenolysis. u.Syph., 198: 111, 1954. S.LINDEREG, 0. AND ERNSTER, L.: Chemistry Thepresence of DNAin the nucleus in amounts and Physiology of Mitoehondria and Micro- comparableto those in basal cell nuclei indicates somes. Springer-Verlag, Wien, 1954. that granular cells are fully functional. 9. RICRTERICH, ROLAND: Enzymopathologie. D. Cells of the stratum lueidum and the horny cells Mitoehondrien, pags. 42—45 etc. Springer- Verlag, Berlin, GOttingen, Heidelberg, 1958. obviously deriving from granular cells do not10. For results of modern research on mitochon- contain mitochondria either, and insofar as dna; see Symposium: The Structure and bio- chemistry of mitoehondria. J. Histoehem. they have any metabolism this is apparently and Cytoehem., 1: 179—276, 1953. nnoxybiotic. 11. WARBIJEG, 0.: Uber die Entstehung der Krebs- Thus, the epidermis can be divided into two zellen, Die Naturwissensehaften, 42: 401, 1955—Pfitigers Arch. f.d.ges. Physiol., 154: biologically highly different zones. The proximal 599,1913; 158: 19, 189, 1914. zone consisting of basal- and prickle-cell layers12. HoaEBooM, H. GEORGE, SCHNEIDER, WALTER C.ANDSTEIRBICH, MART Jo: Localization is oxybiotic and may be designated as stratum and integration of cellular functions. Cancer oxybioticum. The distal zone consisting of granular Research, 13: 617, 1953..
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