title: [Comparative study of the cells of the freshwater planarian Polycelis tenuis (Iijima) using dissociated fragments cultivated in vitro: ultrastructural aspects and incorporation of (3H) leucine and (3H) uridine].
abstract: Study of planaria cells, which are the result of dissociated fragments cultivated in vitro, allows the evolution of two cell groups to be followed: (1) Differentiated cells, which do not divide, and do not dedifferentiate either, incorporate leucine and uridine at a rate which remains stable for the whole duration of the culture. (2) Undifferentiated cells have a mitotic and incorporation rate of leucine and uridine which varies during the period of culture. After 10 days of culture they demonstrate the characteristics of cells undergoing differentiation. These results are in agreement with those of other authors who attribute an essential role to undifferentiated cells during regeneration of the adult planaria.
mesh_terms: D000818:Animals; D002454:Cell Differentiation; D002467:Cell Nucleus / Q000648:ultrastructure; D002478:Cells, Cultured; D003594:Cytoplasmic Granules / Q000648:ultrastructure; D004721:Endoplasmic Reticulum / Q000648:ultrastructure; D007930:Leucine / Q000378:metabolism; D008854:Microscopy, Electron; D008938:Mitosis; D010932:Planarians / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D012038:Regeneration; D013997:Time Factors; D014419:Turbellaria / Q000166:cytology*; D014529:Uridine / Q000378:metabolism
chemical_list: D007930:Leucine; D014529:Uridine
vernacular_title: Etude comparative de l'évolution des cellules de planaires d'eau douce Polycelis tenuis (Iijima) dans des fragments dissociés en culture in vitro aspects ultrastructuraux, incorporations de leucine et d'uridine tritiée