Development of the actin and the cytokeratin cytoskeletons of parietal cells during differentiation of the rat gastric mucosa.
Available evidence strongly suggests that microfilaments and cytokeratin intermediate filaments (IF) play a role in the reorganization of the luminal pole required for the secretion of acid by parietal cells. To correlate the organization of both cytoskeletal systems with the differentiation of the secretory membranes of parietal cells, the distribution of F-actin and cytokeratin was studied during the ontogenic development of the rat. Primitive parietal cells were detected with parietal cells autoantibodies and ultrastructurally by transmission electron microscopy (TEM). The distribution of IF and of F-actin in differentiating parietal cells was determined using anticytokeratin antibodies and FITC-phalloidin, respectively. Development of both cytoskeletal systems was followed by TEM. Ultrastructurally, parietal cells are identified from day 19 on, by the presence of an incipient canaliculus, which later enlarges and fills with microvilli. No intracellular tubulovesicular system is observed. Using parietal cells autoantibodies these cells are detected from day 20 on. Immunocytochemistry and TEM demonstrate that parietal cells possess organized cytokeratin and actin cytoskeletons, which develop further as differentiation proceeds. At birth, parietal cells show an ultrastructure and a distribution of IF and microfilaments similar to that of differentiated cells. In newly born rats, the F-actin cytoskeleton redistributes after suckling. This reorganization results from an enlargement of the canalicular lumen, filled with microvilli rich in actin. Thus, functional maturation of parietal cells is paralleled by the development of organized IF and F-actin cytoskeletons associated to the secretory surface.
Departamento de Biología Celular y Molecular, Facultad de Ciencias Biológicas, Pontificia Universidad Católica de Chile, Santiago. mdabike@genes.bio.puc.cl
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Dabiké
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Koenig
D000199:Actins / Q000032:analysis*; D000367:Age Factors; D000818:Animals; D002454:Cell Differentiation; D003599:Cytoskeleton / Q000737:chemistry*; D005260:Female; D005753:Gastric Mucosa / Q000166:cytology* / Q000648:ultrastructure; D007150:Immunohistochemistry; D007382:Intermediate Filaments / Q000737:chemistry; D007633:Keratins / Q000032:analysis*; D008297:Male; D008854:Microscopy, Electron; D010295:Parietal Cells, Gastric / Q000648:ultrastructure*; D051381:Rats; D017207:Rats, Sprague-Dawley
D000199:Actins; D007633:Keratins