Some Characteristics of the Anti-Estrous Factor in Lithospermum.

Abstract

The anti-estrous factor of Lithospermum appears to reside in the neutral water fraction. It is most abundant in the flowers and seeds of the dried plant, and almost wholly absent from the stems. Interference with estrus is stopped almost immediately, regardless of the length of treatment, when Lithospermum is withdrawn and animals returned to normal diet. The C3H strain is more sensitive to Lithospermum than is the Rockland Swiss strain. The action of Lithospermum is unlike that of thiouracil. The factor induces no observable changes in the anterior pituitary, thyroid, suprarenals, or pancreas; some atresia is observed in the ovaries, and some atrophy of the uteri.