Lung microRNA Profiling Across the Estrous Cycle in Ozone-exposed Mice

This method can help answer key questions in the lung-immunity field about how to assess the expression of microRNAs that are predicted to regulate inflammatory genes within the lung. This technique offers the simple way for identifying the contributions of circulating hormones to lung microRNA expression. To assess the estrous cycle stage, manually restrain an eight to nine-week-old female mouse and introduce the tip of a plastic 10-microliter pipette filled with ultra pure water into the vagina.

Gently flush four to five times to collect a sample, and deposit the final flush of vaginal fluid onto a glass slide. Then observe the unstained vaginal flush under a light microscope at 20X magnification. For ozone and filtered air exposures, place a maximum of four mice into one of two individual 1.2 liter glass containers with wire mesh lids.