کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
9186527 1579588 2005 7 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Effects of intermittent hypoxia on sympathetic activity and blood pressure in humans
موضوعات مرتبط
علوم زیستی و بیوفناوری علم عصب شناسی علوم اعصاب سلولی و مولکولی
پیش نمایش صفحه اول مقاله
Effects of intermittent hypoxia on sympathetic activity and blood pressure in humans
چکیده انگلیسی
Sympathetic nerve activity and arterial pressure are frequently elevated in patients with obstructive sleep apnea (OSA). The mechanisms responsible for chronic sympathetic activation and hypertension in OSA are unknown. To determine whether repetitive apneas raise sympathetic nerve activity and/or arterial pressure, awake and healthy young subjects performed voluntary end-expiratory apneas for 20 s per min for 30 min (room air apneas). To accentuate intermittent hypoxia, in a separate group of subjects, hypoxic gas (inspired O2 10%) was added to the inspiratory port for 20 s before each apnea (hypoxic apneas). Mean arterial pressure (MAP) and muscle sympathetic nerve activity (MSNA, peroneal microneurography) were determined before and up to 30 min following the repetitive apneas. Following 30 hypoxic apneas (O2 saturation nadir 83.1 ± 1.2%), MSNA increased from 17.4 ± 2.7 to 23.4 ± 2.5 bursts/min and from 164 ± 28 to 240 ± 35 arbitrary units respectively (P < 0.01 for both; n = 10) and remained elevated while MAP increased transiently from 80.5 ± 3.7 to 83.1 ± 3.9 mm Hg (P < 0.05; n = 11). In contrast, in the subjects who performed repetitive apneas during room air exposure (O2 saturation nadir 95.1 ± 0.8%), MAP and MSNA did not change (n = 8). End-tidal CO2 post-apnea, an index of apnea-induced hypercapnia, was similar in the 2 groups. In a separate control group, no effect of time on MAP or MSNA was noted (n = 7). Thus, repetitive hypoxic apneas result in sustained sympathetic activation and a transient elevation of blood pressure. These effects appear to be due to intermittent hypoxia and may play a role in the sympathetic activation and hypertension in OSA.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Autonomic Neuroscience - Volume 121, Issues 1–2, 31 August 2005, Pages 87-93
نویسندگان
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