Rabot S, Szylit O, Nugon-Baudon L, Meslin J C, Vaissade P, Popot F, Viso M
Institut National de la Recherche Agronomique, Unit on Ecology and Physiology of the Digestive Tract, Jouy-en-Josas, France.
Dig Dis Sci. 2000 Sep;45(9):1687-95. doi: 10.1023/a:1005508532629.
The purpose of this work was to assess the influence of microgravity on several endogenous and microbial parameters of digestive physiology. On the occasion of two Spacelab Life Sciences missions, SLS-1 (a 9-day space flight) and SLS-2 (a 14-day space flight), Sprague-Dawley rats flown aboard the US space shuttle were compared to age-matched ground-based controls. In both flights, exposure to microgravity modified cecal fermentation: concentration and profile of short-chain fatty acids were altered, whereas urea and ammonia remained unchanged. Only in SLS-1 was there an induction of intestinal glutathione-S-transferase. Additional analyses in SLS-2 showed a decrease of hepatic CYP450 and of colonic goblet cells containing neutral mucin. After a postflight recovery period equal to the mission length, only modifications of the hepatic and intestinal xenobiotic metabolizing enzymes still persisted. These findings should help to predict the alterations of digestive physiology and detoxification potential likely to occur in astronauts. Their possible influence on health is discussed.
这项工作的目的是评估微重力对消化生理学的几个内源性和微生物参数的影响。在美国国家航空航天局太空实验室生命科学任务的两次飞行任务中，即太空实验室生命科学-1（为期9天的太空飞行）和太空实验室生命科学-2（为期14天的太空飞行），将搭乘美国航天飞机飞行的斯普拉格-道利大鼠与年龄匹配的地面对照组进行了比较。在这两次飞行中，暴露于微重力环境均改变了盲肠发酵：短链脂肪酸的浓度和分布发生了变化，而尿素和氨则保持不变。仅在太空实验室生命科学-1飞行任务中出现了肠道谷胱甘肽-S-转移酶的诱导。太空实验室生命科学-2飞行任务中的进一步分析显示，肝脏细胞色素P450以及含有中性粘蛋白的结肠杯状细胞数量减少。在等于飞行任务时长的飞行后恢复期后，仅肝脏和肠道的外源性物质代谢酶的改变仍然存在。这些发现应有助于预测宇航员可能出现的消化生理学改变和解毒潜力。文中还讨论了它们对健康可能产生的影响。
