Langille B L, Osberg C
Can J Physiol Pharmacol. 1985 Sep;63(9):1057-64. doi: 10.1139/y85-173.
Pressure transients resulting from square-wave changes in abdominal aortic blood flow rate were used to derive effective arterial compliance and peripheral resistance of the hind-limb circulation of anaesthetized rabbits. The model for deriving these parameters proved applicable if step changes in flow were kept less than 35% of mean flow. Under resting conditions, the effective hind-limb arterial compliance of normal rabbits averaged 3.46 X 10(-3) mL/mmHg (1 mmHg = 133.322 Pa). Hind-limb arterial compliance decreased with increasing pressure at low arterial pressures, but unlike compliance of isolated arterial segments, compliance did not vary at and above normal resting pressures. Baroreflex destimulation (bilateral carotid artery occlusion) caused an increase in effective hind-limb vascular resistance at 48.4% and a decrease of arterial compliance of 50.7%, so that the constant for flow-induced arterial pressure changes (resistance times compliance) was largely unchanged. Similarly, the arterial time constant for rabbits with chronic hypertension was similar to that for controls because threefold increases in hind-limb vascular resistance were offset by decreases in compliance. Reflex-induced decreases in arterial compliance are probably mediated by sympathetic nerves, whereas decreases associated with hypertension are related to wall hypertrophy in conjunction with increased vasomotor tone. Arterial compliance decreased with increasing pressure in hypertensive animals, but this effect was less pronounced than in normotensive rabbits.
利用腹主动脉血流速率方波变化产生的压力瞬变来推导麻醉兔后肢循环的有效动脉顺应性和外周阻力。如果血流的阶跃变化保持在平均血流的35%以下，那么用于推导这些参数的模型被证明是适用的。在静息状态下，正常兔的有效后肢动脉顺应性平均为3.46×10(-3) mL/mmHg（1 mmHg = 133.322 Pa）。在低动脉压时，后肢动脉顺应性随压力升高而降低，但与离体动脉段的顺应性不同，在正常静息压力及以上时，顺应性没有变化。压力感受性反射去刺激（双侧颈动脉闭塞）导致有效后肢血管阻力增加48.4%，动脉顺应性降低50.7%，因此血流诱导的动脉压变化常数（阻力乘以顺应性）基本不变。同样，慢性高血压兔的动脉时间常数与对照组相似，因为后肢血管阻力增加三倍被顺应性降低所抵消。反射引起的动脉顺应性降低可能由交感神经介导，而与高血压相关的降低与血管壁肥厚以及血管运动张力增加有关。在高血压动物中，动脉顺应性随压力升高而降低，但这种效应不如正常血压兔明显。
