Identification of motoneurons supplying the tensor veli palatini muscle in the guinea pig and cat: an horseradish peroxidase study.

Identification of motoneurons supplying the tensor veli palatini muscle was attempted by the horseradish peroxidase (HRP) method in the guinea pig and cat. After HRP injection into the tensor veli palatini muscle, HRP-labeled neurons were seen in the regions closely medial to the cluster of the lateral pterygoid motoneurons in the dorsolateral division of the trigeminal motor nucleus. In the guinea pig the tensor veli palatini motoneurons were observed at the level of the whole rostrocaudal extent of the trigeminal motor nucleus, while in the cat they were seen at the level of the rostral two-thirds of the nucleus.