不同海拔高原低压缺氧环境下大鼠肠道病理损伤特点

目的:探讨不同海拔高度的高原低压缺氧环境下大鼠肠道病理损伤的特点。方法:将30只SD雄性大鼠随机分5组:平原对照组、5000米海拔高度10天组、5000米海拔高度21天组、6500米海拔高度10天组、6500米海拔高度21天组,每组6只。大鼠在平原环境或模拟高原环境中常规饲养,在相应时间点,深度麻醉受试大鼠致死,取材,固定、HE染色后镜检并进行病理学损伤评分。结果:各高原组空、回肠病理损伤评分均显著高于平原对照组(P0.01),5000 m暴露21d组空肠、回肠、结肠病理损伤评分显著高于5000 m暴露10 d组,明显低于6500 m暴露21d组,6500 m暴露10d组空肠、回肠、结肠病理损伤评分显著高于5000 m暴露10 d组(P0.01或P0.05)。5000 m暴露10 d组结肠损伤病理评分与平原对照组比较差异无统计学意义外,其余高原组结肠病理损伤评分均显著高于平原对照组(P0.01或P0.05)。5000 m暴露21 d组空肠与结肠病理损伤评分存在显著性差异(P0.05);6500 m暴露21 d组空肠和回结肠均与结肠病理损伤评分存在显著性差异(P0.05,P0.01)。结论:肠道粘膜随着海拔高度和缺氧时间的延长而损伤加重。在相同的情况下,小肠的损伤较结肠严重,但空肠和回肠的损伤无明显差异,结肠损伤的发生较晚且与高原环境停留时间具有明显关系,提示在进入高原早期应将小肠病理损伤的防治作为重点。

Characteristics of Pathological Injury of Intestinal Tract in Rats under Hypobaric Hypoxia Environment at Different High Altitude

ABSTRACT Objective: To study the characteristics of intestinal tract pathological injury of rats in hypobaric hypoxia at different high altitude. Methods: 30 male SD rats were randomly divided into 5 groups: Plain group (n=6), High-altitude (HA) 5000 m for 10 day group(n=6), HA 5000 m for 21day group(n=6), HA 6500 m for 10day group(n=6), HA 6500 m for 21day group (n=6). Rats were raised normally either in plain or simulated high altitude environment, at the corresponding time point, rats were euthanized, small intestines were harvested, fixed tissues were processed routinely into paraffin and sections were stained routinely with hematoxylin and eosin. Mor- phologic parameters were measured by optical microscope and then the pathological injury score were evaluated. Results: The patho- logical injury scores of jejunum and ileum in the high altitude group were significantly higher than that of the plain group(P<0.01), the pathological injury scores of jejunum, ileum and colon were significantly higher in the HA 5000 m for 21 day group than that of the HA 5000 m for 10 day group, but significant lower than that of the HA 6500 m for 21 day group, the pathological injury scores of jejunum, ileum and colon were significantly higher in the HA 6500 m for 10 day group than that of the HA 5000 m for 10 day group(P<0.01,P<0.05). The pathological injury scores of colon were significantly higher in the groups of the high altitude than the plain group except for the HA 5000 m for 10 day group(P<0.01, P<0.05). The pathological injury scores of jejunum had significant different with that of the colon in the HA 5000 m for 21 day group(P<0.05); the pathological injury scores of both jejunum and ileum had significant different with that of the colon in the HA 6500 m for 21 day group(P<0.05, P<0.01). Conclusion: The injuries of the intestinal mucosa became serious with the with rising altitude and the stayed time, the intestinal injuries were more serious than that of colon at same situation, however there were no significant different between jejunum and ileum, the injuries of colon happened later than intestine, and they correlated with the stay time in the high altitude, which indicated that intestinal injury should be pay more attention in the early time of entering the hypobaric hypoxia environment of the high altitude.