Biology of Reproduction, Vol 15, 519-522, Copyright © 1976 by Society for the Study of Reproduction

Copper IUD-Induced Loss of Endometrial Arylamidase Activity in the Rabbit

¹ Abteilung Anatomie der RWTH, D-5100 Aachen, West Germany

Copper IUDs of blastocyst size cause, in the rabbit uterine epithelium, local reduction of activity of amino acid arylamidase, an aminopeptidase type enzyme found in the endometrium and in uterine secretion during preimplantation phases. By this means (although evidently by a different mechanism, namely direct enzyme inhibition) copper IUDs mimic an effect exerted by the late preimplantation and early implantation stage blastocyst which locally stimulate discharge of this enzyme from the uterine epithelium into the uterine secretion. The effect has not been seen in experiments with copper-free IUDs and hormone-containing IUDs.

Note:
ACKNOWLEDGMENTS The author wishes to cordially thank his colleagues Dr. Ursula Mootz and W.-D. Schultz for help with the laparotomies and making the copper beads, and Prof. Dr. W. Koberg for permission to use his dental laboratory. Sincere thanks are due to Mrs. Anneliese Leonhardt, Gerda Bohr and Petra Moeller for excellent technical assistance. Prostaglandins were kindly provided by Dr. H. Vorbrüggen (Schering AG, Berlin). This investigation was supported by Deutsche Forschungsgemeinschaft grant De 181/4.