Mucociliary clearance in health and disease
Cold air
In cold conditions, the nose has to work harder to warm the inhaled air as it is arriving at lower temperatures than usual. Due to the cold, the blood vessels supplying the goblet cells in the epithelium of the nasal passages dilate, bringing more blood to the area. This results in an increased production of mucous and liquid which overwhelms normal mucociliary clearance, causing your nose to drip or run. Once the temperature of inspired air increases, your nose will stop running as the blood vessels will vasoconstrict, decreasing the production of mucous and liquid in the nasal passages.
Summary:
- Cold air needs to be warmed and humidified
- Dilation of blood vessels supplying goblet cells
- Increased production of mucous and liquid
- Overwhelms normal mucociliary clearance
