Manaker S, Zucchi P C
Department of Medicine, University of Pennsylvania School of Medicine, Philadelphia 19104-4283, USA.
Synapse. 1998 Jan;28(1):44-59. doi: 10.1002/(SICI)1098-2396(199801)28:1<44::AID-SYN6>3.0.CO;2-C.
The hypoglossal and motor trigeminal nuclei contain somatic motoneurons innervating the tongue, jaw, and palate. These two cranial motor nuclei are myotopically organized and contain neurotransmitter binding sites for thyrotropin-releasing hormone, substance P, and serotonin. Quantitative autoradiography was used to localize thyrotropin-releasing hormone, substance P, and serotonin-1A and serotonin-1B binding sites in the hypoglossal and motor trigeminal nuclei and to relate the relative distributions of these binding sites to the myotopic organizations of the two nuclei. In the hypoglossal nucleus, high-to-moderate concentrations of all four binding sites were present in the dorsal and ventromedial subnuclei, whereas low concentrations were noted in the ventrolateral subnucleus. In the motor trigeminal nucleus, high concentrations of serotonin-1B, moderate densities of thyrotropin-releasing hormone, and low levels of substance P and serotonin-1A binding sites were present in both the ventromedial and dorsolateral subnuclei. These observations demonstrate that neurotransmitter binding sites in the hypoglossal and motor trigeminal nuclei are heterogeneously localized and that their distributions correspond to the previously described myotopic organizations of each nucleus.
舌下神经核和三叉神经运动核包含支配舌头、下颌和腭的躯体运动神经元。这两个颅运动核按肌局部定位组织排列，并含有促甲状腺激素释放激素、P物质和5-羟色胺的神经递质结合位点。采用定量放射自显影法来定位舌下神经核和三叉神经运动核中的促甲状腺激素释放激素、P物质以及5-羟色胺-1A和5-羟色胺-1B结合位点，并将这些结合位点的相对分布与这两个核的肌局部定位组织排列联系起来。在舌下神经核中，背侧和腹内侧亚核存在高到中等浓度的所有四种结合位点，而腹外侧亚核中的浓度较低。在三叉神经运动核中，腹内侧和背外侧亚核均存在高浓度的5-羟色胺-1B、中等密度的促甲状腺激素释放激素以及低水平的P物质和5-羟色胺-1A结合位点。这些观察结果表明，舌下神经核和三叉神经运动核中的神经递质结合位点呈异质性定位，且它们的分布与先前描述的每个核的肌局部定位组织排列相对应。
