Biology of Reproduction, Vol 3, 342-346, Copyright © 1970 by Society for the Study of Reproduction

Studies on the Relation of Decidual Cell Response to Luteal Maintenance in the Pseudopregnant Rat

¹ West Virginia University, Morgantown, West Virginia, 26506

The relation of the decidual cell response (DCR) to the life span of corpora lutea was studied in three experiments on pseudopregnant rats. The first experiment with five groups of 12 rats each was conducted to see if there was a local effect of a DCR on luteal maintenance. The DCR was induced on Day 4 of pseudopregnancy (morning of vaginal plug = Day 0). The groups and mean lengths of pseudopregnancy (in days) were as follows: (I) sham operation: 14.3; (II) unilateral DCR: 18.4; (III) bilateral DCR: 19.4; (IV) unilateral DCR and ipsilateral unilateral ovariectomy: 14.7; (V) unilateral DCR and contralateral unilateral ovariectomy: 18.2. Groups II,III, and V differed (p < .05) from groups I and III but not from each other. A second experiment showed that pelvic neurectomy did not abolish the increase in luteal life span due to either hysterectomy or a bilateral DCR in rats. A third experiment was performed to determine if uterine distention without a DCR would alter the length of pseudopregnancy. Cylindrical glass rods were placed in one or both uterine horns on Day 1 of pseudopregnancy. No differences in the mean length of pseudopregnancy were detected when these two groups were compared with controls. It was concluded that the DCR has a local effect on the life span of corpora lutea, and that the lengthening of pseudopregnancy due to a DCR was not abolished by pelvic neurectomy, and was not the result of uterine distention.