Ito Hisao, Nishibayashi Mitsuru, Kawabata Keigo, Maeda Seishi, Seki Makoto, Ebukuro Susumu
The Institute of Experimental Animal Sciences, Hyogo College of Medicine, Mukogawa-cho 1-1, Hyogo 663-8501, Nishinomiya, Japan.
Auton Neurosci. 2003 Aug 29;107(1):1-8. doi: 10.1016/S1566-0702(03)00026-2.
To clarify the anatomical location of medullary neurons associated with vomiting, the musk shrew (Suncus murinus), a small animal used as a model for emesis, was exposed to various emetic stimuli and patterns of neuronal excitation were investigated by Fos immunohistochemistry. In motion experiments, musk shrews were shaken for 30 min on a tabletop shaker (displacement=25 mm and frequency=1.2 Hz). Ten of fifteen animals vomited frequently (Mo-FV group); the other five animals did not vomit (Mo-NV group). In radiation experiments, X-ray irradiation (10 Gy) of the whole body caused frequent vomiting in all of seven experimental animals (Ra-FV group). In the Mo-FV group, many Fos-immunoreactive (Fos-ir) neurons were detected in the nucleus of the solitary tract (NTS) and the reticular formation. The distribution pattern of Fos-ir neurons in the Mo-NV group was similar to that in the Mo-FV group, but the Mo-NV group had significantly fewer positive neurons in the NTS and the reticular formation around the nucleus ambiguus. In the Ra-FV group, numerous Fos-ir neurons were observed in the area postrema, an area containing no positive neurons in the motion-stimulated animals. The number of Fos-ir neurons in the NTS of the Ra-FV group was not statistically different from that of the Mo-NV group. In the Mo-FV and Ra-FV groups, Fos-ir neurons were clustered in the reticular formation at the dorsal-dorsomedial edge of the nucleus ambiguus at the level of the rostral medulla, while few such clusters were observed in the Mo-NV group. These neurons may play a role in the regulation of the vomiting response.
为明确与呕吐相关的延髓神经元的解剖位置，将作为呕吐模型的小动物麝鼩暴露于各种催吐刺激下，并通过Fos免疫组织化学研究神经元兴奋模式。在运动实验中，将麝鼩放在桌面振荡器上摇晃30分钟（位移=25毫米，频率=1.2赫兹）。15只动物中有10只频繁呕吐（运动-频繁呕吐组）；另外5只动物未呕吐（运动-不呕吐组）。在辐射实验中，全身X射线照射（10 Gy）导致所有7只实验动物频繁呕吐（辐射-频繁呕吐组）。在运动-频繁呕吐组中，在孤束核（NTS）和网状结构中检测到许多Fos免疫反应性（Fos-ir）神经元。运动-不呕吐组中Fos-ir神经元的分布模式与运动-频繁呕吐组相似，但运动-不呕吐组在NTS和疑核周围的网状结构中的阳性神经元明显较少。在辐射-频繁呕吐组中，在最后区观察到大量Fos-ir神经元，在运动刺激动物中该区域没有阳性神经元。辐射-频繁呕吐组NTS中Fos-ir神经元的数量与运动-不呕吐组无统计学差异。在运动-频繁呕吐组和辐射-频繁呕吐组中，Fos-ir神经元聚集在延髓头端水平疑核背-背内侧边缘的网状结构中，而在运动-不呕吐组中很少观察到这种聚集。这些神经元可能在呕吐反应的调节中起作用。
