低氧暴露下高原鼠兔血液中三种内源性气体分子含量的变化

Changes of Three Endogenous Gas Molecules in the Blood of Plateau Pika Exposed to Hypoxia

内源性NO和CO以及H_(2)S是目前发现的三种气体信号分子,在血管收缩调节和血管重构反应中发挥重要作用,影响肺血管收缩反应(HPV)。本实验模拟5 000 m海拔高度,对高原鼠兔(Ochotona curzoniae)和SD大鼠进行不同时间的低氧处理,分别测定平均肺动脉压、右心指数和血液中内源性NO和CO以及H_(2)S的浓度,以揭示三种气体分子在高原鼠兔低氧适应中的作用。研究结果显示:(1)随着低氧时间的增加,高原鼠兔肺动脉压没有出现显著性差异(P>0.05),右心指数并未出现显著性变化(P>0.05);SD大鼠肺动脉压在低氧7 d时出现极显著性增加(P<0.01),并且随着低氧时间的增加肺动脉压持续升高,右心指数出现极显著性增加(P<0.01);(2)高原鼠兔和SD大鼠血液中CO的水平在各处理间维持相对稳定(P>0.05)。高原鼠兔在低氧7 d时血液中NO浓度出现极显著性增加(P<0.01),低氧21 d时NO浓度又恢复到正常水平(P>0.05);SD大鼠在低氧1 d时血液中NO浓度出现显著性降低(P<0.05),低氧7 d和21 d时NO浓度又恢复到正常水平(P>0.05)。高原鼠兔在低氧1 d时血液中H_(2)S浓度无显著性差异(P>0.05),低氧7 d和21 d H_(2)S浓度出现极显著性增加(P<0.01);SD大鼠在低氧1 d时血液中H_(2)S浓度出现极显著性增加(P<0.01),低氧7 d、21 d H_(2)S浓度与正常水平相比显著性降低(P<0.05)。结果表明,高原鼠兔提高血液中H_(2)S的水平可能对其维持正常的肺动脉压和氧气传输具有重要作用。

Endogenous NO, CO and H_(2)S are the three gas signal molecules currently discovered, which play an important role in vasoconstriction regulation and vascular remodeling reactions, affecting hypoxic pulmonary vasoconstriction(HPV). In this experiment, the altitude of 5 000 m was simulated, and the plateau pika(Ochotona curzoniae) and the SD rat were treated with hypoxia at different times, to measure the mean pulmonary artery pressure, right heart index, and the concentration of endogenous NO, CO, and H_(2)S in the blood to reveal the role of three gas molecules in hypoxic adaptation of plateau pika. The results showed that:(1) With the increase of hypoxic time, there was no significant difference in pulmonary artery pressure of plateau pika(P>0.05), and there was no significant change in right heart index(P>0.05). Pulmonary arterial pressure in SD rat was hypoxia. There was a very significant increase in 7 days(P<0.01), and the pulmonary artery pressure increased with the increase of hypoxic time, and the right heart index showed a significant increase(P<0.01);(2) The levels of CO in the blood of plateau pika and SD rat remained relatively stable between treatments(P>0.05). The NO concentration in the blood of plateau pika significantly increased at 7 days of hypoxia(P<0.01), and the NO concentration returned to normal level at21 days of hypoxia(P>0.05). SD rat was in the blood with hypoxia for one day. The concentration of NO decreased significantly(P<0.05), and the NO concentration returned to normal level at 7 and 21 days of hypoxia(P>0.05).There was no significant difference in H_(2)S concentration in the blood of plateau pika at one day of hypoxia(P>0.05), and there was a significant increase in H_(2)S concentration at 7 and 21 days of hypoxia(P<0.01). SD rat was exposed to hypoxia for one day. The concentration of H_(2)S in the blood increased significantly(P<0.01), and the concentration of H_(2)S in hypoxic 7 days and 21 days decreased significantly compared with the normal level(P<0.05).The results indicated that increasing the level of H_(2)S in the blood of plateau pika may play an important role in maintaining normal pulmonary artery pressure and oxygen transmission.