The classical progesterone receptor mediates the rapid reduction of fallopian tube ciliary beat frequency by progesterone
1 Institute of Neuroscience and Physiology, the Sahlgrenska Academy , University of Gothenburg, SE-405 30 Göteborg, Sweden
2 Department of Physics, University of Gothenburg, SE-412 96 Göteborg, Sweden
3 Department of Infectious Diseases, Institute of Biomedicine, the Sahlgrenska academy, University of Gothenburg, Guldhedsgatan 10, SE-413 46 Göteborg, Sweden
Reproductive Biology and Endocrinology 2013, 11:33 doi:10.1186/1477-7827-11-33Published: 8 May 2013
The transport of gametes as well as the zygote is facilitated by motile cilia lining the inside of the fallopian tube. Progesterone reduces the ciliary beat frequency within 30 minutes in both cows and mice. This rapid reduction suggest the involvement of a non-genomic signaling mechanism, although it is not known which receptors that are involved. Here we investigated the possible involvement of the classical progesterone receptor in this process.
The ciliary beat frequency of mice fallopian tube was measured ex vivo using an inverted bright field microscope and a high speed camera. The effects of the agonists progesterone and promegestone and an antagonist, mifeprestone, were investigated in wildtype mice. The effect of progesterone was also investigated in mice lacking the classical progesterone receptor.
Progesterone, as well as the more specific PR agonist promegestone, significantly reduced the CBF at concentrations of 10–100 nanomolar within 10–30 minutes. In the absence of progesterone, the PR antagonist mifeprestone had no effect on the ciliary beat frequency at a concentration of 1 micromolar. When ciliated cells were pre-incubated with 1 micromolar mifeprestone, addition of progesterone did not reduce the ciliary beat frequency. Accordingly, in ciliated cells from mice not expressing the classical progesterone receptor, exposure to 100 nanomolar progesterone did not reduce the ciliary beat frequency.
This is the first study to provide comprehensive evidence that the classical progesterone receptor mediates the rapid reduction of the tubal ciliary beat frequency by progesterone.