Permeability and Weibel-Palade Bodies of the Blood Vessels in the Human Vocal Fold Mucosa

Objectives: Transendothelial exchange and permeability of the capillaries in Reinke space (the superficial layer of the lamina propria) of the vocal fold mucosa affect physiological and pathological conditions of the human vocal fold mucosa. The mechanism of permeability and Weibel-Palade bodies of the blood vessels in the human vocal fold mucosa were investigated using electron microscopy.

Study design: Histologic analysis of the human vocal fold.

Methods: Six normal human vocal folds (three adults and three newborns) obtained from autopsy cases and three human vocal folds with Reinke edema from surgical specimens were investigated under transmission electron microscopy.

Results: There were three possible capillary wall transport systems related to the permeability of the blood vessels in the vocal fold mucosa: 1) Fenestra transport, plasma exuded from the capillaries into surrounding tissue via the fenestration with or without a diaphragm; 2) vesicular transport (transcellular transport via vesicles), the use of vesicles to ferry fluid and solutes across endothelial cells; and 3) junctional transport (intercellular transport), molecules passed through intercellular gaps between endothelial cells. Weibel-Palade bodies were present in the cytoplasm of endothelial cells both in adults and newborns. They were present in high numbers in the cytoplasm of endothelial cells, with intercellular transport in the vocal folds with Reinke edema.

Conclusion: There were three types of mechanisms for the permeability of the blood vessels in the human vocal fold mucosa. Some physiologically active substances, such as histamine produced by Weibel-Palade bodies, may adversely influence the permeability of the blood vessels.

Level of evidence: NA. Laryngoscope, 2588-2592, 2018.