RELEASE OF LUTEINIZING HORMONE FROM THE ANTERIOR HYPOPHYSIS BY AN ACETYLCHOLINE-LIKE SUBSTANCE FROM THE HYPOTHALAMIC REGION

Abstract

The direct application of an acetyl-choline-prostigmine mixture to the exposed pituitary glands of rats resulted in pseudopregnancy, as judged by a persistent diestrus smear and histologically confirmed deciduomata at the site of uterine trauma. Evidence was offered that the effect of the acetylcholine-prostigmine mixture in causing a release of luteinizing hormone from the ant. pituitary was a direct and specific local action in the gland. Direct atropinization of the exposed pituitary glands of rats inhibited the pseudopregnancy which normally followed electrical stimulation of the uterine cervix. From this, together with the reports of previous work of others as to the non-essential nature of the nervous connections in the pituitary stalk, it is concluded that there is probably an acetylcholine-like humoral transmission between the hypothalamic region and the ant. hypophysis. These results offer a reasonable explanation for part of the previously demonstrated effect of prostigmine in precipitating menstrual flow in $? suffering from "nervous" amenorrhea.