Endocrinology, Vol 112, 2181-2186, Copyright © 1983 by Endocrine Society

ARTICLES

The role of decidual tissue in the development of the dependency on luteinizing hormone in the rat corpus luteum

MS Nanes, WK Morishige and I Rothchild

In pregnant rats, treatment with an antiserum to LH (LHAS) on days 2-5 inclusive (early LHAS treatment; day 1 = insemination) delayed implantation by about 4 days. The appearance of the dependency of the corpora lutea on LH for the maintenance of progesterone secretion (LH dependency), as determined by the rate of fall in progesterone secretion after a single test injection of LHAS, was also delayed by 4 days. Treatment with a small amount of estradiol on either day 4 or days 4-9 prevented the delay in both implantation and LH dependency. Implantation thus prevented early LHAS treatment from delaying LH dependency, but its effect seems to have been due to decidualization, which accompanies implantation in the rat. In decidual tissue (DT)- bearing pseudopregnant rats, early LHAS treatment delayed LH dependency for only 1 day, while it delayed LH dependency for at least 3 days in ordinary pseudopregnant rats and for at least 4 days in hysterectomized pseudopregnant rats. Estrogen itself seems to have prevented the delay in LH dependency only by inducing implantation, since it had no effect in the DT-bearing pseudopregnant rats. How DT affects the corpus luteum's dependency on LH is unknown, but it may be related to whatever effect DT has on prostaglandin production in the endometrium.