CELLULAR DIFFERENCES IN THE REGENERATION OF MURINE SKELETAL-MUSCLE - A QUANTITATIVE HISTOLOGICAL STUDY IN SJL/J AND BALB/C MICE

Christopher Mitchell, JK MCGEACHIE, MD GROUNDS

Research output: Contribution to journalArticle

85 Citations (Scopus)

Abstract

Skeletal muscle regeneration in SJL/J and BALB/c mice subjected to identical crush injuries is markedly different: in SJL/J mice myotubes almost completely replace damaged myofibres, whereas BALB/c mice develop fibrotic scar tissue and few myotubes. To determine the cellular changes which contribute to these differential responses to injury, samples of crushed tibialis anterior muscles taken from SJL/J and BALB/c mice between 1 and 10 days after injury were analysed by light and electron microscopy, and by autoradiography. Longitudinal muscle sections revealed about a 2-fold greater total mononuclear cell density in SJL/J than BALB/c mice at 2 to 3 days after injury. Electron micrographs identified a similar proportion of cell types at 3 days after injury. Autoradiographic studies showed that the proportions of replicating mononuclear cells in both strains were similar: therefore greater absolute numbers of cells (including muscle precursors and macrophages) were proliferating in SJL/J muscle. Removal of necrotic muscle debris in SJL/J mice was rapid and extensive, and by 6 to 8 days multinucleated myotubes occupied a large part of the lesion. By contrast, phagocytosis was less effective in BALB/c mice, myotube formation was minimal, and fibrotic tissue conspicuous. These data indicate that the increased mononuclear cell density, more efficient removal of necrotic muscle, together with a greater capacity for myotube formation in SJL/J mice, contribute to the more successful muscle regeneration seen after injury.
Original languageEnglish
Pages (from-to)159-166
JournalCell and Tissue Research
Volume269
Issue number1
Publication statusPublished - Jul 1992

Fingerprint Dive into the research topics of 'CELLULAR DIFFERENCES IN THE REGENERATION OF MURINE SKELETAL-MUSCLE - A QUANTITATIVE HISTOLOGICAL STUDY IN SJL/J AND BALB/C MICE'. Together they form a unique fingerprint.

  • Cite this