Phospholipases a of Krebs II Ascites Cells: Specificity, Release and Subcellular Localization
The phenomenon of contact inhibition has proved to be closely related to growth control. It was demonstrated that insensibility of cells in culture to contact inhibition is proportional to their malignancy in animals (6). In attempting to define the biochemical basis of contact inhibition, attention has naturally centered on the cell surface and its components, and particularly on phospholipids. It was stated that virus-transformed cells, thus having malignant potentialities renewed their phospholipids at a greater rate than normal controls. Among the enzymes of the plasma membrane, the phospholipases A have been mainly studied in normal hepatocyte (5) (11) and in cells infected with measles virus (8). We have a poor knowledge of them in the neoplastic cell and their role in the cell membrane is not clear. Therefore we investigated the specificity Al or A2 the intracellular distribution and the release in the extracellular environment of phospholipases A in Krebs II ascites tumor cells, maintained in female Swiss strain mice (9–12 weeks aged) by weekly intraperitoneal transfer of ascitic fluid.
KeywordsAscitic Fluid Measle Virus Contact Inhibition Normal Hepatocyte Fatty Acid Moieities
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