Mitochondria-rich cells of frog skin in transport mechanisms: morphological and kinetic studies on transepithelial excretion of methylene blue.
The following study combines histological observations on the localization and density of mitochondria-rich cells with a kinetic study of the part played by these cells in transport phenomena. In the ventral skin, mitochondria-rich cells and granular cells are equally abundant in the first living cell layer. The mitochondria-rich cells were shown to excrete methylene blue [3,9-bis-(dimethylamino)-phenozathionum chloride]. A kinetic study of this excretion across the isolated epithelium of Rana esculenta skin showed that the mechanism of the excretion was a saturable one. An important fraction of methylene blue excretion depends on the absorption of sodium; the absence of this ion, or the inhibition of its transport by ouabain or amiloride, inhibits the excretion of the organic base. The mitochondria-rich cells, however, do not appear to play a determining role in sodium transport.
D000818:Animals; D001692:Biological Transport; D004847:Epithelial Cells; D004848:Epithelium / Q000378:metabolism; D008751:Methylene Blue / Q000378:metabolism*; D008928:Mitochondria / Q000378:metabolism*; D011893:Rana esculenta / Q000378:metabolism*; D012867:Skin / Q000378:metabolism* / Q000648:ultrastructure; D012964:Sodium / Q000378:metabolism
D012964:Sodium; D008751:Methylene Blue