title: Quantitation of binding and subcellular distribution of Clostridium perfringens enterotoxin in rat liver cells.
abstract: Binding of enterotoxin from Clostridium perfringens type A was studied in suspensions of parenchymal and nonparenchymal cells from rat liver. In hepatocytes, 1.5 X 10(6) specific binding sites per cell with an association constant of 3.2 X 10(6) M-1 were found. About 1% of the added toxin was nonspecifically bound to the hepatocytes. At concentrations of toxin below 0.1 micrograms/ml, 80% of the toxin density of 7 X 10(6) cells per ml. Binding did not increase after the cells became permeable to the toxin. Subcellular fractionation in a sucrose gradient produced no evidence for binding to parts of the cell other than the plasma membrane. The degree of binding to nonparenchymal cells was less than 10% of the binding to hepatocytes.
mesh_terms: D000818:Animals; D001665:Binding Sites; D002118:Calcium / Q000378:metabolism; D002470:Cell Survival; D003015:Clostridium Infections / Q000378:metabolism / Q000401:mortality; D003016:Clostridium perfringens; D004533:Egtazic Acid / Q000494:pharmacology; D004727:Endothelium / Q000166:cytology / Q000378:metabolism; D004768:Enterotoxins / Q000378:metabolism*; D007728:Kupffer Cells / Q000378:metabolism; D008099:Liver / Q000166:cytology / Q000378:metabolism; D051381:Rats; D013347:Subcellular Fractions / Q000032:analysis
chemical_list: D004768:Enterotoxins; D004533:Egtazic Acid; D002118:Calcium