, Volume 383, Issue 1–3, pp 111–116 | Cite as

Inhibition of regeneration in the planarian Dugesia polychroa (Schmidt) by treatment with magnesium chloride: a morphological study of wound closure

  • Wolfgang SchürmannEmail author
  • Roland Peter


At a concentration of 0.2% (21 m M) in culture water, magnesium chloride impaired muscle contraction and completely inhibited head regeneration in specimens of Dugesia polychroa cut prepharyngeally. The wound stayed open for nine days, with neoblasts accumulating beneath the wound without any signs of differentiation. Extremely delayed wound closure occurred by spreading epithelial cells, and was completed after 30 days in the magnesium chloride solution. Histological examination confirmed the absence of any regenerated head structures. Interestingly, the inhibitory effect was removed when such headless fragments were cut once more and kept in normal culture water: complete head regeneration then occurred at a normal rate. Among several possible explanations for the failure to regenerate, the following hypothesis is an attractive alternative: direct contact between parenchyma and epithelial cells during the period following injury seems to be an essential stimulus for the start of cell differentiation within the blastema, and the lack of such contact as a result of the drug action prevents normal regeneration. When the wound has eventually closed, a continuous basement membrane separates epithelium from parenchyma. Thus a direct contact between these tissues is never established.

Dugesia polychroa magnesium chloride neoblasts planarians regeneration wound healing Platyhelminthes 


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Copyright information

© Kluwer Academic Publishers 1998

Authors and Affiliations

  1. 1.Department of Genetics and General BiologyUniversity of SalzburgSalzburgAustria

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