Tehran Azad University, Faculty of Pharmaceutical Sciences
Uterine contractions can occur either in the non-pregnant state (during the menstrual cycle and delivery of sperm to the fallopian tubes) or in the pregnant state, specifically at the time of delivery. However, the pattern of contraction regarding the parameters of the frequency, amplitude, and duration are different in the non-pregnant and pregnant uterus.
Most of the studies on uterine activity are limited to in vitro measurements of smooth muscle tension. The in vitro organ bath made important contributions to the current knowledge of physiology and pharmacology, including receptor affinities and the discovery of many therapeutic agents. Indeed, this technique is considered to be the preferred method to identify global physio-pharmacological aspects of smooth muscle activity. However, this technique is not comprehensive, and in vivo approaches are still very critical for the evaluation of whole uterine tissue responses as an organ to understand physiological responses.
Biomedical telemetry provides a platform to monitor and study human and animal physiological functions from a remote site with wireless transmission and minimal disturbance to normal activity. Miniature advanced radio-telemetric transmitters enabled researchers to comprehensively study the intrauterine pressure in vivo. To track the intrauterine pressure in rodents, the catheter which is attached to the transmitter can be implanted under aseptic conditions either in pregnant or non-pregnant animals. The optimized model could successfully track the changes of intrauterine pressure which reflect uterine motility during pregnancy, delivery, and estrous cycle in the pregnant and non-pregnant state.
This method collection describes a set of in vitro and in vivo techniques that can potentially be used to answer certain pharmacological questions and methodological problems associated with uterine physiology and contraction in response to a new chemical entity during the pregnant, postpartum, and non-pregnant states. This method collection can be extended to study smooth muscle response of the other organs, such as the bladder.