Conducting bronchioles are formed from the early divisions of the subsegmental bronchi within the bronchial tree. Histologically, their epithelium resembles that of the bronchi in that there are:
- ciliated pseudostratified columnar cells
- goblet cells
- basal cells
- brush cells
- dense core granule cells
However, the cartilage has now disappeared from the outer section of their walls and in the same layers, spirally-orientated smooth muscle fibres become more apparent. With progression along the conducting bronchioles, the ciliated pseudostratified epithelium is replaced by a cuboidal ciliated epithelium.
The conducting bronchioles are continous with the terminal bronchioles.
Last reviewed 01/2018