低氧对高原鼠兔和大鼠血液NO 与ET-1的影响

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。

Effect of hypoxia on nitric oxide and endothelin-1 in pikas and rats

The aim of the present study was to compare the effects of hypoxia on NO,ET ~(-1) and NO/ET ~(-1) levels in Wistar rats and pikas. We determined NO and ET ~(-1) levels 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 entry to high altitude, the NO and ET ~(-1) levels in rats were markedly increased compared to those in pikas (respectively, P<0.01), whereas the values of NO/ET ~(-1) in rats and pikas were very close (P>0.05). There was a decreasing trend in NO levels and an increasing trend in ET ~(-1) levels (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 ~(-1) levels 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) levles in Wistar rats and pikas at 3 780 m are very different, may indicate adaption or acclimitization to high altitude hypoxia.