Objective: To investigate expression of the constitutive androstane receptor (CAR) in the pregnant rat cervix.
Methods: Rat uterine tissue was obtained on gestational days 12, 16, 20, 21, and 22 (the day of parturition), and postpartum day 1. In addition, liver, lung, kidney, heart, and skeletal muscle tissue were obtained. Expression of the two known CAR isoforms was evaluated using reverse transcriptase-polymerase chain reaction.
Results: These studies confirmed CAR expression in the liver; however, CAR was not demonstrated in the myometrium or cervical tissue.
Conclusions: The currently described CAR1 and CAR2 isoforms are not expressed in rat uterine tissue; therefore, they do not appear to participate in parturition in the pregnant rat.