Bonanni Enrica, Pasquali Livia, Manca Maria Laura, Maestri Michelangelo, Prontera Concetta, Fabbrini Monica, Berrettini Stefano, Zucchelli Giancarlo, Siciliano Gabriele, Murri Luigi
Neurological Clinic, Department of Neurosciences, University of Pisa, Via Roma 67, Pisa 56126, Italy.
Sleep Med. 2004 Mar;5(2):137-45. doi: 10.1016/j.sleep.2003.08.009.
The aim of the study was to evaluate the catecholaminergic activity and lactate concentration during exercise in normotensive patients with obstructive sleep apnoea syndrome (OSAS).
Thirteen normotensive patients affected by OSAS (mean age+/-standard error (SE), 52.6+/-2.8 yrs; mean apnoea-hypopnea index, 35.7+/-20.3) were enrolled in the study. Night-polysomnography and multiple sleep latency test in the sleep laboratory were performed for every patient. Patients also underwent an incremental workload exercise on a cycloergometer. We evaluated plasma epinephrine and norepinephrine levels in aerobic exercise conditions, relating them to lactate levels.
Analysis of the venous lactate curve showed that exercise lactate levels were significantly higher (peak normalised levels, 782 vs. 270%; P<0.001 ), and an earlier lactate threshold was detected, in the patients compared to normal controls. While plasma catecholamine levels were abnormally high in almost all patients at rest, exercise values were not significantly different from controls. Lactate/norepinephrine and lactate/epinephrine area ratios were significantly higher in OSAS subjects than in controls (2.25 vs. 1.21 and 2.37 vs. 1.03, respectively).
The results indicate that abnormal production of lactate during exercise occurs in OSAS, possibly due to some muscular metabolic modification. While catecholaminergic activity is abnormally increased at rest, this activity does not seem to play a significant role in lactate concentration during exercise in these patients.
本研究旨在评估阻塞性睡眠呼吸暂停综合征（OSAS）的血压正常患者运动期间的儿茶酚胺能活性及乳酸浓度。
本研究纳入了13例受OSAS影响的血压正常患者（平均年龄±标准误（SE），52.6±2.8岁；平均呼吸暂停低通气指数，35.7±20.3）。对每位患者进行了睡眠实验室的夜间多导睡眠图及多次睡眠潜伏期测试。患者还在功率自行车上进行了递增负荷运动。我们评估了有氧运动条件下血浆肾上腺素和去甲肾上腺素水平，并将其与乳酸水平相关联。
静脉乳酸曲线分析显示，与正常对照组相比，患者运动时的乳酸水平显著更高（峰值标准化水平，782%对270%；P<0.001），且检测到更早的乳酸阈值。虽然几乎所有患者静息时血浆儿茶酚胺水平异常升高，但运动时的值与对照组无显著差异。OSAS受试者的乳酸/去甲肾上腺素和乳酸/肾上腺素面积比显著高于对照组（分别为2.25对1.21和2.37对1.03）。
结果表明，OSAS患者运动期间乳酸产生异常，可能是由于某些肌肉代谢改变所致。虽然静息时儿茶酚胺能活性异常增加，但这种活性在这些患者运动期间的乳酸浓度方面似乎并不起重要作用。
