Related Experiment Video
Updated: Jul 6, 2026
Ultrasonography in Experimental Reproductive Investigations on Rats
Published on: December 2, 2017
Progesterone, estrogen and pregnancy do not decrease colon myoelectric activity in rats: an in vivo study
L B M Speranzini1, P P Lopasso, A A Laudanna
1Laboratory of Clinical Investigation LIM 07, Department of Gastroenterology, University of São Paulo School of Medicine, São Paulo, Brazil. manlio.sp@uol.com.br
Background:
Progesterone, estrogen and the hormonal complex of pregnancy have been responsible for some degree of colon hypomotility in human pregnancy.
Objective:
To find out if estrogen, progesterone and the hormonal complex of pregnancy decrease colon myoelectric activity.
Methods:
The study was performed in 37 healthy female rats in which electrodes were implanted on the serosa of the proximal ascendent, distal ascendent, transverse, and descendent colon. We analyzed the records of colon myoelectric activity in vivo in five groups: control, ovariectomized, ovariectomized and treated with estrogen, ovariectomized and treated with progesterone, and pregnant rats.
Results:
We found a great variation in myoelectric activity in all groups studied. The mean of electric activity did not show statistical difference among the five groups, but pregnant rats had a statistically significant higher duration of maximum electric activity in all distances from the cecocolon junction.
Conclusion:
Pregnant rats had a statistically higher duration of maximum electric activity. If we could transpose these results to humans, this increase in duration of colon myoelectric activity could explain, in part, the slight constipation that some pregnant women have.
More Related Videos
09:01Performing Vaginal Lavage, Crystal Violet Staining, and Vaginal Cytological Evaluation for Mouse Estrous Cycle Staging Identification
Published on: September 15, 2012
06:49Methods for Studying Uterine Contributions to Pregnancy Establishment in an Ovariectomized Mouse Model
Published on: April 7, 2023