低氧对高原鼠兔和大鼠血液NO与ET_(-1)的影响(英文)

Effect of hypoxia on nitric oxide and endothelin_(^(-1)) in pikas and rats

将Wistar大鼠暴露于3 780 m低氧环境,分别于24 h、2 wk及3 wk后采用酶联免疫法和硝酸还原酶法测定血液中的ET^(-1)和NO的含量,计算NO/ET^(-1)值,并与高原鼠兔比较,探讨低氧条件下大鼠与高原鼠兔血液中NO与ET^(-1)含量的变化趋势。结果表明,低氧24 h后,大鼠血液中NO和ET^(-1)的含量显著高于同海拔的高原鼠兔(P<0·01),而NO/ET^(-1)值无显著差异(P>0·05)。随着大鼠在高海拔停留时间的延长,血液中NO含量呈减少趋势,而ET^(-1)则有上升趋势,二者呈显著的负相关(r2=0·2416,P<0·01)。高原鼠兔NO/ET^(-1)值约为大鼠低氧2 wk和3 wk的2倍(P<0·01)。说明不同低氧暴露时间,高原鼠兔和大鼠的NO、ET^(-1)及NO/ET^(-1)值有显著差异,提示NO/ET^(-1)值可以作为有机体是否适应高原低氧环境的一个指标。

The aim of the present study was to compare the effects of hypoxia on NO, ET-1 and NO/ET-1levels in Wistar rats and pikas. We determined NO and ET-1levels in the serum of 30 rats （three groups of 10 rats, each taken to 3 780 m and divided into 24 h, 2 wk and 3 wk durations） and 10 pikas at 3 780 m by ELISA and Nitrate Reductase Method. We compared the values of NO, ET -1 and NO/ET-1 in rats of 24 h duration with those in rats of 2 wk and 3 wk durations. We then compared NO, ET-1 and NO/ET-1 values in the 24 h, 2 wk, 3 wk groups with those in pikas. In the beginning of en- try to high altitude, the NO and ET-1levels in rats were markedly increased compared to those in pikas （respectively, P 〈 0. 01 ）, whereas the values of NO/ET-lin rats and pikas were very close （P 〉0.05）. There was a decreasing trend in NO levels and an increasing trend in ET-1levels （respectively, P 〈0. 01 ） with passage of time at high altitude in rats, and NO was well correlated with ET-1 （ r^2 -0. 2416, P 〈0. 01 ）. The NO/ET-11evels in pikas was approximately 2 fold greater than in the 2 wk and 3 wk groups （ P 〈 0.01 ）. In conclusion, NO, ET-1 and NO/ET -1 levies in Wistar rats and pikas at 3 780 m are very different, may indicate adaption or acclimitization to high altitude hypoxia.