[The physical properties, pharmacology and antifertility action of crystal trichosanthin protein liposome].

The crystal trichosanthin protein liposome (TPL) was prepared by an emulsion-forming method. The rate of entrapment was 33.0-44.8% and the rate of recovery was 95.15-99.58%. The determination of trichosanthin protein was accomplished by spectrophotometry at 650 nm, thus eliminating completely the interference of lipids. The distribution of particle size of TPL was mainly in the range of 1-2 microns (96.9%). TPL was sterilized by 60Co radiation at 4 degrees C for 90 min and was stable when stored at 4 degrees C, 25 degrees C and 37 degrees C. The seepage rate of trichosanthin from the liposome was 15.22% after storage for 38 days at room temperature. Experiments showed that TPL had a slight allergic reaction, but was safe by hemolysis and coagulation tests. When the mice were given TPL ip 8 micrograms per animal 6 days after pregnancy, the rate of termination of early pregnancy was 83.3%. It thus appears that TPL can terminate early pregnancy in mice distinctly. This indicates that TPL may be expected to be developed into a new type of anti-early pregnancy preparation.