Borison H L
Aviat Space Environ Med. 1985 Jan;56(1):66-8.
The emetic chemoreceptor trigger zone (CTZ), located in the area postrema of the medulla oblongata, is generally believed to be indispensable for the vomiting in motion sickness and, by extrapolation, also in space sickness. Accordingly, it has been postulated that a "motion vomiting substance" is secreted into the cerebrospinal fluid in the emetic process. Furthermore, certain therapeutic measures against motion sickness are aimed at preventing the presumed chemical stimulation of the CTZ. This concept originated from laboratory experiments in which ablation of the area postrema protected some dogs and monkeys against motion-induced vomiting. More recent experiments, however, showed that verified lesions of the area postrema were not effective in preventing motion sickness in cats. It appears that an indispensable unidentified element close to but separate from the area postrema was fortuitously destroyed in the earlier experiments. The overall evidence leads to the conclusion that the area postrema is not essential for motion-induced vomiting. Therefore, no functional basis exists for the postulation of a motion vomiting substance, and it is irrational for the treatment of motion sickness to seek pharmacologic blocking agents that act at the CTZ.
催吐化学感受区（CTZ）位于延髓的最后区，一般认为它对于晕动病呕吐必不可少，由此推断，对太空病呕吐也必不可少。因此，有人推测在催吐过程中有“晕动呕吐物质”分泌到脑脊液中。此外，某些抗晕动病的治疗措施旨在防止推测的对CTZ的化学刺激。这一概念源于实验室实验，在这些实验中，切除最后区可保护一些狗和猴子免受运动诱发的呕吐。然而，最近的实验表明，经证实的最后区损伤对预防猫的晕动病无效。看来，在早期实验中，一个靠近最后区但与之分离的不可或缺的未知因素被意外破坏了。总体证据得出结论，最后区对于运动诱发的呕吐并非必不可少。因此，假设存在晕动呕吐物质没有功能基础，而且寻求作用于CTZ的药理阻断剂来治疗晕动病是不合理的。
