In vivo and in vitro observation of nasal ciliary motion in a guinea pig model

In vivo visualization and analysis of ciliary motion in allergic rhinitis models induced by ovalbumin

Due to the lack of an assessment approach, the image of in vivo nasal ciliary motion of allergic rhinitis (AR) has never been captured and analyzed to date. Here, we have used an optimized approach to analyze the nasal ciliary function in vivo in AR rats. The digital microscopy system, a method for direct observation of ciliary motion in a living AR rat model, was applied to visualize and measure ciliary motion in vivo, including ciliary beat frequency (CBF) and ciliary beat distance (CBD). The AR rat model was established by ovalbumin sensitization. Comparisons of nasal ciliary motion in vivo between the experimental group (ovalbumin sensitization, allergen, or histamine) and the control group were analyzed. In the living rat model of allergic rhinitis, CBF and CBD decreased to 57.8 and 73.1% of the control group, respectively, but were restored after administration of chlorpheniramine maleate. Ovalbumin (OVA) significantly inhibited the ciliary motion of normal mucosa in vivo. However, responding to the OVA challenge, the ciliary motion of OVA-sensitized mucosa would not decrease further and stay at a stable level. Histamine stimulated in vivo ciliary motion quickly within 30 min, but afterward, the ciliary motion gradually decreased below the baseline. These results have clarified that in vivo ciliary motion was impaired by nasal mucosal sensitization, and this impairment was most likely related to allergen challenge and histamine. In addition, the short-term stimulation and long-term inhibition effects of histamine on in vivo ciliary motion were first reported in this study.