Zoccal Daniel B, Bonagamba Leni G H, Antunes-Rodrigues José, Machado Benedito H
Department of Physiology, School of Medicine of Ribeirão Preto, University of São Paulo, 14049-900, Ribeirão Preto, SP, Brazil.
Auton Neurosci. 2007 Jul 31;134(1-2):115-7. doi: 10.1016/j.autneu.2007.01.004. Epub 2007 Feb 9.
In the present study we investigated whether plasma corticosterone is altered in rats exposed to chronic intermittent hypoxia (CIH). Rats were submitted to a fraction of inspired oxygen of 6%, for 40 s, every 9 min, 8 h a day, for 35 days (CIH rats, n=17), while control rats were maintained under normoxic conditions (n=16). After CIH, the rats presented a significant increase in baseline mean arterial pressure (118+/-2 vs 106+/-3, mmHg) but not in baseline heart rate (381+/-17 vs 362+/-12 bpm) when compared to the control rats. Besides, a significant increase in plasma corticosterone was observed in CIH rats in comparison to the control rats (39+/-4 vs 20+/-2 microg/dl). Considering that corticosterone can affect both peripheral and central sympathetic mechanisms, the elevated plasma corticosterone may represent a new insight on the mechanisms underlying the hypertension observed after CIH.
在本研究中，我们调查了暴露于慢性间歇性低氧（CIH）的大鼠血浆皮质酮是否发生改变。大鼠每天8小时，每9分钟接受一次6%的吸入氧，持续40秒，共35天（CIH大鼠，n = 17），而对照大鼠维持在常氧条件下（n = 16）。CIH后，与对照大鼠相比，大鼠的基线平均动脉压显著升高（118±2对106±3，mmHg），但基线心率无显著变化（381±17对362±12 bpm）。此外，与对照大鼠相比，CIH大鼠的血浆皮质酮显著增加（39±4对20±2 μg/dl）。考虑到皮质酮可影响外周和中枢交感神经机制，血浆皮质酮升高可能为CIH后观察到的高血压潜在机制提供新的见解。
