| Popis: |
In former investigations the development of sarcoma was observed in several mice injected subcutaneously with various solutions of ovarian hormones, or with liver extract prepared for the treatment of pernicious anemia. As far as epithelial tissues are concerned, ovarian hormones induce a cancerous transformation only in the secondary sex organs, in which they cause rhythmic growth during the sexual cycle, or during pregnancy. This suggested that the factors causing the development of sarcoma might be less specific than those which induce the formation of carcinoma. In order to test this conclusion further, a number of mice were injected with solutions of substances which are not considered carcinogenic. Fifty-five mice were injected subcutaneously for variable lengths of time. Table I shows the substances used for injection and their concentrations, the length of the period of injection, and the results obtained. The age of the mice given in the table is the age at examination at the end of the experiment. The large majority of the animals were males; only a few were females. The injections were given six times a week, except those of estrogen dissolved in oil. In addition to the experiments included in this table, nine mice belonging to strains A, C57, D and AKA were injected subcutaneously for a shorter time, namely for one month, six times a week, with 0.25 c.c. of a saturated solution of cane sugar. In most of these mice acute necrosis developed at the site of injection and the animals became cachectic; the experiment was therefore discontinued. |
