The effect of progesterone and other hormones on the Fallopian tube ciliary beat frequency in mouse

Abstract

The inside of the fallopian tube is covered with epithelial cells. These cells are involved in the transportation of oocytes and sperms in the tube and are important for fertilization to occur. The hormone progesterone has been tested for its effect on the ciliary activity in the fallopian tube and previous studies have shown that progesterone reduces the ciliary beat frequency (CBF). There are (at least) two types of progesterone receptors present in the fallopian tube, the membrane progesterone receptors, mPRs and the nuclear progesterone receptor, nPR. The aim of this study was to examine which of these receptors that regulate the CBF. Different hormones, specific for a certain receptor or group of receptors, were used to measure the CBF in mouse ex vivo. The fallopian tube was dissected and chopped in small pieces for exposure of the cilia. Each tissue sample was investigated based on ciliary activity by an inverted bright field microscope and a high speed camera. After addition of a certain hormone the change in CBF was recorded during 60 minutes. Progesterone with a concentration of 30 nM gave an average decrease in CBF, -1.4 Hz (p=0.03). Promegestone R5020 is an agonist for nPR and gave a reduction in CBF, -3.13 Hz (p=0.0046) for the concentration 100 nM. An agonist for the mPR, substance X, was tested and gave no significant change in CBF. Mifepristone RU486 works as an antagonist for nPR and gave no significant change in CBF. The reduction in CBF by progesterone seen in this study is in agreement with that from previous studies. Reduction in ciliary activity by R5020 gives a clue to the involvement of nPR in the regulation of CBF in the fallopian tube in mouse. Based on the measurements performed in this study the mPR does not seem to be involved in the regulation of CBF.