Related Experiment Video
Updated: Aug 12, 2026
Ultrasonography in Experimental Reproductive Investigations on Rats
Published on: December 2, 2017
A corticotropin releasing hormone receptor antagonist does not delay parturition in rats
E F Funai1, L M O'Neill, A Davidson
1Department of Obstetrics and Gynecology, New York University School of Medicine, USA.
Objective:
To determine the effects of CP-154, 526, a corticotropin releasing hormone (CRH) receptor antagonist, on the length of normal rat gestation.
Study Design:
Twenty-four timed-pregnant Sprague-Dawley rats were purchased for this study. The drug and placebo were administered to the animals using an osmotic pump surgically inserted in the dorsal subcutaneous space. Six animals received 6 mg/kg/day of the drug, six animals received 12 mg/kg/day of the drug and twelve animals received the placebo. The gestational period, weight of each pup and number of pups in each litter were recorded and compared in the drug group versus placebo group.
Results:
No difference was noted in the gestational period of the drug and placebo rats. The mean weight of pups in both the drug and placebo groups was 6.18 g. The number of pups per litter were similar in the drug and placebo groups.
Conclusion:
Antagonism of CRH receptors in rats has no effect on the length of gestational period, pup weight or number of pups per litter. Further studies are needed to define the role of CRH and its antagonism in primate pregnancy, as has been done in sheep.
