The effects of hetero-reinnervation within the rat tongue

This study centred on the effects of hetero-reinnervation within the rat tongue. Lingual, greater auricular and vagus nerves were used. Proximal segments of each of these nerves were joined to the distal hypoglossal stump using 10/0 nylon suture. Histological sections of the tongue were examined. In lingual hypoglossal cross-union, histological evidence indicated that neuromuscular junction (nmj) reinnervation was present to some degree in all intrinsic tongue muscles and within geniohyoid. Lingual nerve fibres were also found within the dorsal keratinised lingual epithelium, reinnervating taste buds and intralingual ganglia. Greater auricular nerve fibres were unable to make contact with nmjs, nor were they found to any appreciable degree within the lingual mucosa. Vagal nerve fibres were found close to, but not innervating, nmjs, but did reinnervate taste buds, lingual vasculature and intralingual ganglia. It was concluded that nodose cells are unable to reinnervate vacated nmjs, but like lingual fibres can reinnervate lingual mucosa, intralingual ganglia and vasculature.