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低压值下体负压（ＬＢＮＰ）可仅使心肺压力感受器卸荷。采用－２ｋＰａＬＢＮＰ实验结果表明：ＬＢＮＰ既不引起动脉血压变化，也不引起心率改变，但却引起基础胸阻抗（Ｚ。）从对照的２１．８±０．４升高到２２．５±０．５Ω（Ｐ＜０．０１），前臂血管阻力（ＦＶＲ）从１２．３±０．９升高到１９．９±１．４Ｕ（Ｐ＜０．０１），前臂血流（ＦＢＦ）从对照时７．１±０．５降低到４．３±０．３ｍｌ·ｍｉｎ￣（－１）·１００ｍｌ￣（－１），心率变异性谱（ＨＲＶ）未发生任何变化，即心肺压力感受器卸荷时心脏自主神经活动水平与均衡性不受影响。由于ＦＶＲ和ＦＢＦ的变化可间接反映外周血管交感传出活动水平，上述实验结果提示，心肺压力感受器对外周血管及心脏自主神经活动的调节可能存在机能分化现象。
Lower body pressure negative body pressure (LBNP) can only unload the cardio-pulmonary baroreceptors. Using -2kPaLBNP results showed that: LBNP did not cause changes in arterial blood pressure, heart rate does not cause change, but caused by the basic chest impedance (Z.) increased from 21.8 ± 0.4 control to 22.5 ± 0. (P <0.01). The forearm vascular resistance (FVR) increased from 12.3 ± 0.9 to 19.9 ± 1.4U (P <0.01) 7.1 ± 0.5 reduced to 4.3 ± 0.3ml · min ~ (-1) · 100ml ~ (-1), heart rate variability spectrum (HRV) did not change any, that is, when the heart and lung baroreceptor unloading Cardiac autonomic activity level and balance are not affected. Because the changes of FVR and FBF can indirectly reflect the level of peripheral vascular sympathetic outflow activity, the above experimental results suggest that there may be a mechanism of differentiation of cardiopulmonary baroreceptor on peripheral blood vessels and cardiac autonomic nervous system.