Functional imaging of mucociliary phenomena: high-speed digital reflection contrast microscopy.

We present a technique for the investigation of mucociliary phenomena on trachea explants under conditions resembling those in the respiratory tract. Using an enhanced reflection contrast, we detect simultaneously the wave-like modulation of the mucus surface by the underlying ciliary activity and the transport of particles embedded in the mucus layer. Digital recordings taken at a speed of 500 frames per second are analyzed by a set of refined data processing algorithms. The simultaneously extracted data include not only ciliary beat frequency and its surface distribution, but also space-time structure of the mucociliary wave field, wave velocity and mucus transport velocity. Furthermore, we propose the analysis of the space and time evolution of the phase of the mucociliary oscillations to be the most direct way to visualize the coordination of the cilia. In particular, this analysis indicates that the synchronization is restricted to patches with varying directions of wave propagation, but the transport direction is strongly correlated with the mean direction of waves. The capabilities of the technique and of the data-processing algorithms are documented by characteristic data obtained from mammalian and avine tracheae.

Ciliary motility in bovine oviducts for sensing rapid non-genomic reactions upon exposure to progesterone.

Based on the expression of hormone receptors, oviductal cells receive a series of signals to control the conduit and transport of gametes. Most cells in the inner oviductal mucosa have motile cilia, and the mucociliary system of oviducts represents a prominent object of study for rapid feedback after application of steroid hormones. Using a high-speed reflectometry method, we investigated effects on the ciliary beat frequency (CBF) of bovine oviductal explants after progesterone treatment. To classify changes of CBF as either classic or non-classic reactions, we pretreated primary tissue cultures with mifepristone, an antagonist to the classic progesterone receptor in a second experimental series. In contrast to classical genomic reactions, non-classic or non-genomic reactions are characterized by fast effects, insensitive to the classic receptor antagonist. We observed inhibitory effects on the ciliary beat frequency as soon as 15 minutes after application of progesterone (20 microM), reaching a plateau of about 11 % after 90 minutes. Pretreatment with mifepristone (20 microM) for two hours did not induce significant differences in short-term reactions. However, the inhibitory influence of progesterone after 24 hours could be effectively prevented. Our data confirmed the short-term reaction of CBF as non-genomic or non-classic.