Early involvement of cyclic nucleotides in the artificially stimulated decidual cell reaction in the mouse uterus. Biol. Reprod

The role of cyclic nucleotides in triggering the decidual cell reaction (DCR) was investigated. All studies involved ovariectomized mice treated with estradiol and progesterone to prepare the uterus for implantation. The right uterine horn was injected intraluminally with chemicals or was physically traumatized. Cyclic AMP levels in the uterus increased slightly during the hormone priming schedule and markedly after the deciduogenic stimulus. Injection of 10 iii of sesame oil produced a 10-fold increase in cAMP in the right horn within 15 mm. There was no change in the cAMP level in the left horn. Cyclic GMP levels increased 6-fold during the progesterone phase of the priming schedule and another 7-fold within 15 mm after sesame oil injection. These changes in cGMP levels occurred in both uterine horns. Treatments found to produce a DCR were intraluminal injections of sesame oil, mineral oil, and cholera toxin (5 zg). Glycerol injection, followed by ligation of the uterus, and crushing of the uterine horn also produced a DCR. All of these treatments elevated the levels of cAMP in the right uterine horn. Sesame oil and mineral oil injections were the only deciduogenic treatments which altered cGMP levels in the uterus. These studies suggest that cAMP functions in triggering the uterine DCR and that cGMP does not