Influence of Pseudopregnancy and Progesterone on the Activity of 5-Nucleotidase in the Uterus of Mice

ŒSTROGENS stimulate the activity of many enzymes present in the uterus of the ovariectomized mouse 1 . Histochemistry reveals the side of enzyme activity; but little is known about changes due to administration of progesterone. A histochemical investigation concerning the activity of a number of enzymes during pseudo-pregnancy and after progesterone administration to castrated mice has shown that in these circumstances marked changes occur. Increased activity of 5-nucleo-tidase in the endometrial stroma and in the myometrium was the most striking change. We used the technique of Wachstein and Meisel 2 .