模拟失重状态下大鼠小肠黏膜光镜及电镜的形态学改变

目的 以尾部悬吊大鼠模型模拟失重的影响,探讨模拟失重是否可引起小肠黏膜的改变. 方法 用光学显微镜和扫描电镜,观察了对照(CON)、尾部悬吊14 d(SUS-14 d)和尾部悬吊21 d(SUS-21 d)大鼠小肠绒毛的超微结构改变. 结果 光镜下SUS-21 d组和SUS-14 d组大鼠小肠黏膜的绒毛高度降低、宽度增加、隐窝变浅,与CON组比较差异有显著性(F=294.24、60.05、328.63,P<0.05);电镜下SUS-21 d组和SUS-14 d组大鼠小肠黏膜的微绒毛高度减低、表面积缩小,微绒毛间的间距增宽,微绒毛糖衣厚度减小,与CON组比较差异有显著性(F=234.90、138.07、104.69、195.35,P<0.01). 结论 模拟失重14 d和21 d,光镜和电镜结果 均提示小肠黏膜可出现绒毛和微绒毛的变稀少,变短、变宽,表面积减小等改变.本工作还提示小肠黏膜微观结构的改变可能是造成航天员在航空飞行中出现腹泻、腹胀等消化和吸收不良症状的重要原因之一.

Changes in optical micrograph and electron micrograph to the mucosa of small intestine of the rats under simulated weightlessness

Objective To investigate if the simulated weightlessness can induce the change in mucosa of small intestinal of tail-suspended rats. Methods Ultrastructural changes of the mucous of small intestinal of 14-day tail-suspended rats (SUS-14 d), 21-day tail-suspended rats (SUS-21 d) and controlled rats (CON) were studied by optical microscope and transmission electron microscope. Results By optical micrograph, the number of villius and crypt of SUS-14 d and SUS-21 d group were fewer than that of CON group. The height and width of villus of SUS-14 d and SUS-21 d group were lower than those in CON group (F=294.24, 328. 63, P<0. 01). The depth of crypt of SUS-14 d and SUS-21 d group were greater than that in CON group (F=60. 5, P<0.01). The ratios of Height/Width and Height/Depth of SUS-14 d and SUS-21 d group were less than that of CON group (F=246.69, 3. 68, P<0. 05). Moreover, by electron micrograph, the number of microvillus was fewer than that in CON group too. The height, superficial area of microvillus and the thickness of icing in SUS-14 d and SUS-21 d group were significantly less than those in CON group (F=234. 90, 138.07, 195. 35, P<0.01). Contrarily, the width of microvillus and the space between every two microvilli in SUS-14 d and SUS-21 d group were greater than those in CON group. Conclusion Results indicate that simulated weightlessness for 14 days and 21 days could lead to the mucosal villi of small intestinal fewer, shorter and wider according to optical micrograph. The analysis also shows that the height and surface area of microvillus are significantly decreased under simulated weightlessness aecording to electron micrograph. These data probably provide important theoretical evidence for finding the reason of aerial diseases such as diarrhea, dyspepsia and disorders of digestion, etc.