Further Studies on the Anti-Estrogenic Activity of Yellow Pine Needles

Abstract

The anti-estrogenic activity of yellow pine needles was assessed by using a 6-hr, bioassay procedure employing the laboratory rat. The effect of estradiol-17β on the uterine tissue of ovariectomized animals was diminished or inhibited by the simultaneous injection of prepared extracts of yellow pine needles. The active substance was eluted from a celite-chloroform concentrate mixture with ethyl acetate. Amorphous crystals formed during the cooling of the ethyl acetate eluant failed to exhibit anti-estrogenic activity even at an administration level of 50 gm. dry matter equivalent of the original plant material. Copyright © 1964. American Society of Animal Science . Copyright 1964 by American Society of Animal Science