Olfactory Ensheathing Cells in a Rat Model of Laryngeal Reinnervation

Objectives: Olfactory ensheathing cells have been used successfully for recovery of nervous system lesions. The aim of our study was to determine whether olfactory ensheathing cells from the olfactory bulb or olfactory mucosa were able to improve functional recovery in a laryngeal reinnervation animal model. Methods: Fifty-nine rats were divided into 6 groups. A group without nerve section (group 1; n = 10) and a group without anastomosis (group 2; n = 11) served as controls. Right vagus nerve section and immediate anastomosis (nonselective reinnervation) was performed in 4 other groups, as follows, in group 3 (n = 10), there was selective reinnervation without any addition of substance; groups 4 (n = 10), 5 (n = 10), and 6 (n = 8) received, on the section and anastomosis site, and at the same time, cultivated olfactory bulb, cultivated olfactory mucosa, and noncultivated olfactory mucosa from inbred rats, respectively. Three months later, videolaryngoscopy with vocal fold movement measurements, electromyography, and histologic examination were performed. Results: The best right vocal fold angular movement (3.05 degrees +/- 1.14 degrees) was observed in group 5 with cultivated olfactory mucosa, versus group 3 (-0.28 degrees +/- 1.51 degrees; p = 0.06). The relative angular vocal fold movement was better in group 5 (p = 0.05). The mobility score was 0.6 +/- 0.27 for group 3 and 1.4 +/- 0.31 for group 5 (p = 0.07). Less synkinesis was observed in the reinnervated groups with cell addition, particularly with noncultivated olfactory mucosa (group 6; p = 0.05). Conclusions: Olfactory ensheathing cells obtained from olfactory mucosa cultures seem to improve functional laryngeal reinnervation in a rat model of nonselective vagus nerve section and anastomosis.