Local effects of substance P on respiratory regulation in the rat medulla oblongata.
Local effects of substance P on respiratory regulation in the rat medulla oblongata.
复制标题
P物质对大鼠延髓呼吸调节的局部影响。
DOI：
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复制
发表时间：
1990
影响因子：
3.3
通讯作者：
T. Hedner
中科院分区：
文献类型：
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作者：
Z. Chen;J. Hedner;T. Hedner
在氟烷麻醉大鼠上，观察了P物质（SP）及其拮抗剂[D-Pro 2，D-Trp 7，9]-SP对基础通气的影响。将SP（0.4-1.5 nmol）微量注射到延髓腹外侧（VLM）（延髓细胞核、面神经核、疑核和外侧网状核）或延髓背内侧（DM，孤束核）及其腹侧周围，剂量依赖性地增加潮气量（VT）和/或分钟通气量。在敏感区域，刺激在几分钟内开始，在8-10分钟左右达到峰值，并在注射后30-45分钟内缓慢恢复正常。在VLM部位，VT的增加通常伴随着呼吸频率（f）的降低，而在DM中，f与VT平行增加。此外，在VLM内，呼吸反应模式随SP注射的确定位置而不同。在巨细胞旁核的腹内侧部、腹外侧部和面神经核腹侧观察到吸气时间缩短。相反，当SP沿着面神经核的腹侧部分和腹侧延髓表面附近或直接在腹侧延髓表面上注射或应用时，呼气时间延长。在SP之前或之后应用[D-Pro 2，D-Trp 7，9]SP可完全拮抗SP对通气的兴奋作用。在VLM中给予SP拮抗剂降低了对低氧呼吸的呼吸反应，但在高氧条件下没有引起变化。
The effect of substance P (SP) and the SP antagonist [D-Pro2,D-Trp7,9]-SP on basal ventilation was investigated in halothane-anesthetized rats. Microinjections of SP (0.4-1.5 nmol) into the ventrolateral medulla oblongata (VLM), (nuclei gigantocellularis, facialis, ambiguus, and reticularis lateralis) or into the dorsomedial medulla oblongata (DM, nucleus tractus solitarius) and its ventral surroundings dose dependently increased tidal volume (VT) and/or minute ventilation. In sensitive areas, the ventilatory stimulation was initiated within minutes, peaked around 8-10 min, and slowly returned to normal over 30-45 min after the injection. In the VLM sites, the increase in VT was generally accompanied by a decrease in respiratory frequency (f), whereas in the DM, f increased in parallel with VT. Furthermore, within the VLM, the respiratory response patterns differed with the definite location of the SP injection. A shortening of inspiratory time was observed in the ventromedial part, the ventrolateral portion of the nucleus paragigantocellularis and ventral to the nucleus facialis. In contrast, a lengthening of expiratory time was seen when SP was injected or applied more laterally along the ventral portion of nucleus facialis and near or directly on the ventral medullary surface. Application of [D-Pro2, D-Trp7,9]SP before or after SP completely antagonized the excitatory effects of SP on ventilation. The SP antagonist administered into the VLM decreased the ventilatory response to hypoxic breathing but caused no change during hyperoxic conditions.