Requirements for restitution of the surface epithelium of frog stomach after mucosal injury.
In frog fundic mucosae mounted in Ussing chambers, exposure to luminal 1 M NaCl for 10 min caused a sharp immediate decrease in potential difference, resistance, short circuit current, and acid secretion, but within 4-6 h these readings had returned toward control values. After initial severe destruction of surface epithelial cells, gradual morphologic restitution occurred within 4-6 h. A Ca2+-free nutrient solution and 4 mM ethylenediaminetetraacetic acid administered after injury prevented both physiologic and morphologic restitution. A Ca2+-free nutrient solution administered alone after injury prevented physiologic recovery, but although narrow gaps and lack of tight junctions were found between some cells, there was near-complete epithelial cell coverage. The addition of 2 mM Ca2+ to these tissues 3 h after injury effected rapid recovery of electrophysiologic parameters and a complete closure of the intercellular spaces. Cytochalasin B (3 X 10(-3) M nutrient) prevented physiologic recovery and mucosal restitution. Neither cycloheximide nor colchicine had any effect on the normal process of restitution. Autoradiography of [3H]thymidine incorporation showed no increase in labeling within 4 h of hyperosmolar injury. We conclude that adequate Ca2+ is required for complete restitution of gastric mucosa after hyperosmolar injury, and that restitution occurs by migration of persisting viable gastric pit cells.
D000818:Animals; D001345:Autoradiography; D002118:Calcium / Q000502:physiology; D003078:Colchicine / Q000494:pharmacology; D003513:Cycloheximide / Q000494:pharmacology; D003571:Cytochalasin B / Q000494:pharmacology; D003599:Cytoskeleton / Q000187:drug effects; D004492:Edetic Acid / Q000494:pharmacology; D004848:Epithelium / Q000473:pathology; D005750:Gastric Juice / Q000378:metabolism; D005753:Gastric Mucosa / Q000187:drug effects / Q000378:metabolism / Q000473:pathology*; D066298:In Vitro Techniques; D007365:Intercellular Junctions / Q000187:drug effects; D007930:Leucine / Q000378:metabolism; D008785:Metiamide / Q000494:pharmacology; D008870:Microtubules / Q000187:drug effects; D014176:Protein Biosynthesis; D011892:Rana catesbeiana; D012038:Regeneration; D012462:Saline Solution, Hypertonic; D013936:Thymidine / Q000378:metabolism
D012462:Saline Solution, Hypertonic; D003571:Cytochalasin B; D008785:Metiamide; D003513:Cycloheximide; D004492:Edetic Acid; D007930:Leucine; D003078:Colchicine; D002118:Calcium; D013936:Thymidine