CHOLINESTERASES IN THE MAMMALIAN TONGUE

Acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) have been demonstrated histochemically in the tongues of five Primates and the rabbit. Sensory nerve endings in the tongue, including the subepithelial nerve net, Meissner's corpuscles and the end bulbs of Kraus, contain both AChE and BChE. The intraepithelial nerve endings and the taste buds in the foliate, vallate and fungiform papillae react for AChE only. The postganglionic parasympathetic nerve fibers innervating both the pure mucous and the pure serous glands of the tongue have abundant AChE. In addition to the AChE and BChE activity in their motor end plates, the skeletal muscle fibers of the tongue also have a concentration of cholinesterases at their point of insertion on the lingual fascia which is designated as the cholinesterasic apparatus. The Winkelmann and Schmit silver technique for nerve axoplasm is found to be unreliable for visualizing autonomic nerves.