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PubMed · 6116320

Age-dependent mitogenesis in normal connective tissue cells.

K Norrby·S Bergström·P Druvefors
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Abstract

We have previously described ways to use the mesentery for studies of proliferation in intact tissue. Here we have studied a weak and a strong mitogenic response in the mesentery of rats aged 6--42 weeks, induced by a single intraperitoneal injection of saline or the mast-cell-degranulating drug 48/80. Proliferation was measured by the specific DNA activity, the fraction of fibroblast- and mesothelial-like cells in the S+G2 cell-cycle-phases, and the mitotic index. We also counted the relative number of mast cells in the tissue (normalized to 5,000 fibroblast-like and mesothelial-like cells), since this might influence 48/80-induced mast-cell-mediated proliferation. In old animals there was a decline in the proliferative response and the time required to initiate DNA synthesis was prolonged. This appears to be the first report of such an age-dependent proliferation characteristic in the mesentery, and probably in any connective tissue. The normalized number of mast cells in the mesentery also declined with increasing age.

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Age FactorsAnimalsCell CountConnective Tissue CellsDNAFibroblastsMaleMast CellsMesenteryMitosisRatsJournal Article

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K Norrby, S Bergström, P Druvefors. 1981. Age-dependent mitogenesis in normal connective tissue cells.. https://doi.org/10.1007/bf02912051

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