Two major types of premotoneurons in the feline trigeminal nucleus oralis as demonstrated by intracellular staining with horseradish peroxidase.

摘要: Previous studies suggest that neurons in the dorsomedial subdivisions of trigeminal nucleus oralis (Vo) may contribute, to reflex control jaw movements and modulation sensory information. The present study has addressed this possibility by use intracellular staining with horseradish peroxidase physiologically identified Vo examine functional morphological properties these neurons. Of 14 labeled neurons, eight had axon collaterals terminating exclusively dorsolateral subdivision motor (DL neurons) four its ventromedial (VM neurons); two were not traced. Both groups sent terminal arbors into other nuclei lower brainstem. DL distinguishable from VM their receptive field (RF) location, neuronal position, somadendritic architecture, projections brainstem nuclei. All except for activated noxious stimuli applied tongue, responsive light mechanical stimulation peri- intraoral structures. RFs located more posterior oral structures than those RF nearly all low-threshold was maxillary region, contrast, involved mandibular region. medial or ventral soma size significantly higher Dendritic both could be separated lateral components. ratio dendritic transverse areas vs. later component also issued terminated larger VIM These observations provide new evidence on contribute facial © 1994 Wiley-Liss, Inc.