[Testing synergism between ethinyl estradiol and norethisterone on the histamine-induced deciduoma and vaginal mucification of castrated rats].

Through the histaminic deciduoma test and a vaginal mucification test, we have endeavoured to show that, in spayed female rats there exists a possibility of synergism between ethynylestradiol and pure norethisterone per os. No synergism could be shown in the former test, owing to, or so it seems, a lack of deciduogenic power proper to norethisterone. The latter test showed, indeed, that ethynylestradiol can, in low quantities, bring about a synergism on the mucifying properties of norethisterone, whereas, in large quantities, it creates an antagonism on the aforesaid properties.