The distribution of cells in the upper forelimb of the axolotl, Ambystoma mexicanum

Authors

  • Patrick W. Tank,

    Corresponding author
    1. Center for Pathobiology and Department of Developmental and Cell Biology, University of California, Irvine, California 92717
    • University of Arkansas for Medical Sciences, Department of Anatomy-510, 4301 West Markham, Little Rock, Arkansas 72201
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  • Nigel Holder

    1. Center for Pathobiology and Department of Developmental and Cell Biology, University of California, Irvine, California 92717
    Current affiliation:
    1. Department of Anatomy, Kings College, University of London, Strand, London WC2R 2LS England
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Abstract

The number and relative density of cells in specific regions of the upper forelimb of the axolotl were compared. Selected transverse sections taken from the distal one-third of the upper forelimb were analysed by light microscopy. Comparisons were made between the total numbers of cells observed in each of the major tissue components of the forelimb (epidermis, dermis, muscle, connective tissues and skeletal tissues). Comparisons were also made between the total numbers of cells located in the major limb quadrants (anterior, posterior, dorsal and ventral). In addition, cellular density (cells/mm2) was compared among eight limb sectors. The results indicate that the posterior quadrant of the upper forelimb contains more cells than any other forelimb quadrant. Cellular density did not favor a particular forelimb quadrant. These results suggest that the proposed clumping of positional values in the posterior region of the forelimb in the axolotl (Tank, unpublished data) may correspond to the presence of a larger number of cells in the posterior quadrant, but does not correspond to a higher cellular density in that region of the upper forelimb.

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