Robinson V J, Manyari D E, Tyberg J V, Fick G H, Smith E R
Department of Medicine, University of Calgary, Canada.
Circulation. 1989 Jul;80(1):99-105. doi: 10.1161/01.cir.80.1.99.
Mental arithmetic stress is known to cause forearm arterial dilation, but the venous responses, including possible changes in the volume-pressure relation, have not been defined. Hence, 10 apparently normal subjects, eight men and two women, mean age 46 +/- 9 years, were studied before and during mental arithmetic stress. Changes in forearm venous volume were estimated with 99mTc blood pool scintigraphy. Group variability of this measurement technique was 1.8 +/- 2.3%. A brachial blood pressure cuff was used to obtain venous occluding pressures of 0, 10, 20, and 30 mm Hg. Mental arithmetic stress increased group systolic and diastolic blood pressure from 126 +/- 12 to 152 +/- 20 mm Hg and from 83 +/- 8 to 93 +/- 15 mm Hg, respectively (p less than 0.001). Heart rate increased from a mean of 75 +/- 15 to 85 +/- 17 beats/min (p less than 0.01). There was no evidence of interaction between or nonlinearity of the volume-pressure plots. Linear regression then yielded the equations V = 99.8 + 0.96P before and V = 86.3 + 0.96P during mental arithmetic stress, which represents a 13.5 +/- 1.6% decrease in forearm vascular volume (p less than 0.001). We conclude that 1) a linear relation exists between forearm venous volume and pressure at physiologic pressures before and during mental arithmetic stress; 2) mental arithmetic stress causes forearm venoconstriction; and 3) such venoconstriction takes place by a parallel shift in the volume-pressure relation (i.e., a shift in unstressed venous volume).
已知心算应激会导致前臂动脉扩张，但包括容积 - 压力关系可能变化在内的静脉反应尚未明确。因此，对10名看似正常的受试者（8名男性和2名女性，平均年龄46±9岁）在心算应激前后进行了研究。用99mTc血池闪烁显像术估计前臂静脉容积的变化。该测量技术的组内变异性为1.8±2.3%。使用肱动脉血压袖带获得0、10、20和30 mmHg的静脉闭塞压。心算应激使组收缩压和舒张压分别从126±12 mmHg升至152±20 mmHg，从83±8 mmHg升至93±15 mmHg（p<0.001）。心率从平均75±15次/分钟增至85±17次/分钟（p<0.01）。没有证据表明容积 - 压力图之间存在相互作用或非线性关系。然后通过线性回归得出心算应激前的方程V = 99.8 + 0.96P，应激期间的方程V = 86.3 + 0.96P，这代表前臂血管容积下降了13.5±1.6%（p<0.001）。我们得出结论：1）在心算应激前后的生理压力下，前臂静脉容积与压力之间存在线性关系；2）心算应激导致前臂静脉收缩；3）这种静脉收缩是通过容积 - 压力关系的平行移动（即无应激静脉容积的移动）发生的。
