Bout R G, Dubbeldam J L
Institute of Evolutionary and Ecological Sciences, Leiden University, The Netherlands.
Eur J Morphol. 1994 Aug;32(2-4):134-7.
The trigeminal and facial motor nuclei in the mallard comprise several subnuclei which innervate tongue, jaw and other head muscles. The premotor cells of the subnuclei innervating jaw muscles are distributed in two longitudinal cell columns within the parvocellular reticular formation (RPc). The ventromedial part of RPc contains cells projecting to subnuclei innervating either jaw-closer muscles or jaw-opener muscles. In the dorsolateral part of RPc three subdivisions may be recognized: a rostral part which projects to two trigeminal subnuclei innervating jaw-closer muscles, an intermediate part which does not serve as premotor area for any of the jaw motor subnuclei and a caudal part of RPcdl which projects to the trigeminal and facial motor subnuclei innervating jaw-opener muscles. Exteroceptive information from mechanoreceptors in the beak reaches all three parts of RPCdl. Muscle spindles in jaw-closer muscles may influence the activity of premotor cells of jaw-opener muscles through their projection upon the caudal part of RPcdl.
绿头鸭的三叉神经核和面神经运动核包含几个亚核，这些亚核支配舌头、颌骨及其他头部肌肉。支配颌骨肌肉的亚核的运动前体细胞分布在小细胞网状结构（RPc）内的两个纵向细胞柱中。RPc的腹内侧部分包含投射到支配闭口肌或开口肌的亚核的细胞。在RPc的背外侧部分可识别出三个亚区：一个投射到支配闭口肌的两个三叉神经亚核的吻侧部分，一个不作为任何颌骨运动亚核的运动前区的中间部分，以及RPcdl的尾侧部分，它投射到支配开口肌的三叉神经和面神经运动亚核。来自喙部机械感受器的外感受信息到达RPCdl的所有三个部分。闭口肌中的肌梭可能通过其投射到RPcdl的尾侧部分来影响开口肌运动前细胞的活动。
