Purification and characterization of a lipolytic factor (toxohormone-L) from cell-free fluid of ascites sarcoma 180.

A lipolytic substance in the ascites fluid of mice with Sarcoma 180, called toxohormone-L, was purified and characterized. The lipolytic activity of toxohormone-L was measured in vitro using rat adipose tissue slices. Toxohormone-L, purified approximately 90-fold from the ammonium sulfate fraction, gave a single band on polyacrylamide gel electrophoresis. Its molecular weight was about 75,000, and its isoelectric point was 4.7. Toxohormone-L is heat labile and nondialyzable, but, on its digestion with trypsin, an active fragment that was heat stable and dialyzable was produced. Toxohormone-L is a protein and is also present in the ascites fluid of patients with hepatoma and Grawitz's tumor.