Terbutaline inhibits corticotropin-releasing hormone (CRH) expression in human trophoblast cells

Objective. To evaluate the effect of beta-adrenergic agonists on the regulation of the expression of the placental corticotropin-releasing hormone (CRH) gene. Study design. Term placentae were collected at the time of elective cesarean section, and trophoblast cells were harvested, isolated, and cultured. The isolated trophoblasts were plated, cultured and subsequently treated with cortisol, terbutaline, RU486, or vehicle control. CRH expression, mRNA abundance of CRH, and the housekeeping gene beta-actin were evaluated by Northern blot analysis. Results. Exposure of the trophoblasts to terbutaline (10^-8 M) inhibited the expression of the CRH gene as depicted by Northern blot analysis. Co-addition of terbutaline (10^-8 M) and RU486 (10 ^-6 M) did not block the stimulatory effects of RU486 on placental trophoblast cells. Conclusion. The beta-adrenergic agonist terbutaline inhibits the expression of CRH in human trophoblasts. This finding may provide insight into the mechanism of action of terbutaline as a tocolytic agent.