The otic ganglion and its neural connections in the rat

The precise localisation of the rat otic ganglion and its neuronal connections, particularly those related to salivation, has been established by means of dissection and from a study of histological sections taken serially through the head. The otic ganglion lies medial to the pterygopalatine branch of the internal carotid artery and beneath the trigeminal ganglion from which it is separated by the sphenoid bone. In the rat there is no direct connection between the glossopharyngeal nerve and the otic ganglion, as is the case in man. However, a neural connection between the facial nerve and the otic ganglion and a further connection linking the glossopharyngeal with the facial nerve through which the salivatory axons may pass to reach the otic ganglion is described. A comparison is made of the neural pathways involved in parotid secretion in the rat with those believed to exist in man.