Arterial and cardiopulmonary baroreflexes in 60- to 69- vs. 18- to 36-yr-old humans.
Arterial and cardiopulmonary baroreflexes in 60- to 69- vs. 18- to 36-yr-old humans.
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60 至 69 岁与 18 至 36 岁人类的动脉和心肺压力反射。
DOI：
10.1152/jappl.1996.80.6.1903
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发表时间：
1996
期刊：
影响因子：
--
通讯作者：
Foresman,BH
中科院分区：
文献类型：
--
作者：
Shi,X;Gallagher,KM;Welch-O'Connor,RM;Foresman,BH
本研究旨在检验以下假设：衰老会减弱中枢血容量不足期间的压力反射功能。通过使用心率 (HR) 和平均动脉压 (MAP) 对休息期间颈部压力和吸力以及 -15 托下体负压 (LBNP) 的反应来评估 11 名健康年轻人和 11 名老年人（年龄 60-69 岁）。评估低水平LBNP期间前臂血管阻力对中心静脉压的斜率作为心肺压力反射敏感性的指标。各组之间的基线心血管变量没有显着差异。此外，心肺压力反射（年轻人与老年人分别为-3.6 vs.-3.7单位/mmHg）或颈动脉压力反射（年轻人与老年人分别为-0.39与-0.35beats.min-1.mmHg-1和-0.26与-0.35mmHg/mmHg）敏感性没有组间差异。 LBNP 不会影响 HR 或 MAP，但会降低两组的 CVP 并增加 FVR。仅在年轻受试者中，LBNP 显着增强了颈动脉 HR (-0.47 +/- 0.03beats.min-1.mmHg-1) 和颈动脉 MAP (-0.42 +/- 0.04 mmHg/mmHg) 反射增益。我们得出的结论是，两个年龄组之间的离散压力反射功能没有差异；然而，老年受试者不存在心肺压力感受器与颈动脉压力感受器反射功能的相互作用，这表明来自离散压力感受器的传入神经输入的中枢整合随着年龄的增长而改变。
This study was designed to test the hypothesis that aging diminished baroreflex function during central hypovolemia. Eleven healthy young and eleven older (age 60-69 yr) individuals were assessed by using heart rate (HR) and mean arterial pressure (MAP) responses to neck pressure and suction during rest and lower body negative pressure (LBNP) of -15 Torr. The slope of forearm vascular resistance to central venous pressure during low-level LBNP was assessed as the index of cardiopulmonary baroreflex sensitivity. Baseline cardiovascular variables were not significantly different between the groups. In addition, there was no group difference in cardiopulmonary baroreflex (-3.6 vs. -3.7 units/mmHg for young vs. older, respectively) or carotid baroreflex (-0.39 vs. -0.35 beats.min-1.mmHg-1 and -0.26 vs. -0.35 mmHg/mmHg, for young vs. older, respectively) sensitivity. LBNP did not affect either HR or MAP, whereas it decreased CVP and increased FVR in both groups. LBNP significantly augmented the carotid-HR (-0.47 +/- 0.03 beats.min-1.mmHg-1) and carotid-MAP (-0.42 +/- 0.04 mmHg/mmHg) reflex gains in the young subjects only. We concluded that there was no difference in the discrete baroreflex function between the two age groups; however, the interaction of cardiopulmonary baroreceptors with carotid baroreflex function was absent in the older subjects, suggesting that the central integration of afferent neural inputs from the discrete baroreceptors was altered with aging.