Liao Xue-mei, Yu Qin
Department of Respiratory Medicine, First Hospital, Lanzhou University, Lanzhou 730000, China.
Zhonghua Jie He He Hu Xi Za Zhi. 2005 Jun;28(6):368-71.
To explore the changes and implications of plasma orexin-A levels in patients with obstructive sleep apnea-hypopnea syndrome (OSAHS).
Polysomnography was performed in 30 obese OSAHS patients (OSAHS group), 30 obese subjects (obese group) and 20 normal healthy adults (control group). In both the OSAHS group and the obese group the body mass index (BMI) was higher than 25, and there was no significant difference in BMI. The plasma was deproteinized by chromatography, and the level of orexin-A was determined by radioimmunoassay.
The plasma orexin-A level in the OSAHS group [(9.0 +/- 1.8) ng/L] was significantly higher than those in the obese group [(7.2 +/- 1.4) ng/L, P < 0.01] and the control group [(6.7 +/- 1.6) ng/L, P < 0.01] respectively. Plasma orexin-A levels in patients with OSAHS correlated positively with the AHI (r = 0.639, P < 0.01), and the arousal index (r = 0.435, P < 0.05), but correlated negatively with the lowest oxygen saturation (LSaO(2)) (r = -0.521, P < 0.01) and the mean oxygen saturation (MSaO(2)) (r = -0.589, P < 0.01). The BMI in the OSAHS group and the obese group did not correlate significantly with the orexin-A levels (r = 0.132, P > 0.05).
The plasma orexin-A levels in OSAHS patients are increased which may be caused by repeated nocturnal hypoxia due to OSAHS. Orexin-A may play a crucial role in the regulation of the sleep-arousal process.
探讨阻塞性睡眠呼吸暂停低通气综合征（OSAHS）患者血浆食欲素-A水平的变化及其意义。
对30例肥胖OSAHS患者（OSAHS组）、30例肥胖者（肥胖组）和20例正常健康成年人（对照组）进行多导睡眠图监测。OSAHS组和肥胖组的体重指数（BMI）均高于25，且BMI无显著差异。采用层析法对血浆进行脱蛋白处理，并用放射免疫分析法测定食欲素-A水平。
OSAHS组血浆食欲素-A水平[（9.0±1.8）ng/L]显著高于肥胖组[（7.2±1.4）ng/L，P<0.01]和对照组[（6.7±1.6）ng/L，P<0.01]。OSAHS患者血浆食欲素-A水平与呼吸暂停低通气指数（AHI）呈正相关（r=0.639，P<0.01），与觉醒指数呈正相关（r=0.435，P<0.05），但与最低血氧饱和度（LSaO₂）呈负相关（r=-0.521，P<0.01），与平均血氧饱和度（MSaO₂）呈负相关（r=-0.589，P<0.01）。OSAHS组和肥胖组的BMI与食欲素-A水平无显著相关性（r=0.132，P>0.05）。
OSAHS患者血浆食欲素-A水平升高，可能是由OSAHS导致的夜间反复缺氧引起的。食欲素-A可能在睡眠-觉醒过程的调节中起关键作用。
