POSTCOITAL ANTIFERTILITY ACTIVITY OF AMINOALCOHOLS

Previously, postcoital antifertility effects of a number of aminoalcoh ols, including 2-(isopropylamino)-ethanol, have been demonstrated in r odents. In this experiment, we compared the antifertility activity of 2-(isopropylamino)-ethanol to the following analogs: hydroxyethylpiper idine, hydroxyethylpiridine, hydroxyethylpirrolidine, and hydroxyethyl pirrolidone Female rats were gavaged on Days 0 through 5 of gestation with 0.7 mmol/kg/d of these substances. Only 2-(isopropylamino)-ethano l and hydroxyethylpirrolidine showed a strong antifertility activity: females treated with 2-(isopropylamino)-ethanol had no signs of implan tation, whereas those treated with hydroxyethylpirrolidine had 100% ea rly resorptions. Treatments with these two substances during the perii mplantation period (Days 4 and 5) produced 100% early resorptions. His tologic examination of the implantation sites showed signs of embryoni c degeneration starting from Day 6.5 of gestation. The flushing of the uteri of females treated with 2-(isopropylamino)-ethanol on Days 0 th rough 3 post coitum showed 78% of the embryos at the stage of 1 to 3 b lastomeres, whereas the embryos of females treated during the same per iod with hydroxyethylpirrolidine were normal blastocysts, Therefore, 2 -(isopropylamino)ethanol and hydroxyethylpirrolidine are able to kill embryos during the early implantation stages, whereas 2-(isopropylamin o)-ethanol is also able to stop the development of preimplantation emb ryos. (C) 1998 Elsevier Science Inc.