Mancini M, De Chiara S, Postiglione A, Ferrara L A
Institute of Internal Medicine and Metabolic Diseases, 2nd Medical School, University of Naples, Italy.
Artery. 1993;20(4):231-41.
Acetazolamide (AZ), the selective inhibitor of carbonic anhydrase, was proved by intravenous Xenon 133 technique to increase cerebral blood flow (CBF). In this study cerebrovascular reactivity to AZ was evaluated in 10 normal subjects by transcranial Doppler (TCD) within the middle cerebral artery (MCA), since several reports have demonstrated that velocity of cerebral blood flow is well correlated to CBF. After 1 gr AZ injection blood flow velocity markedly increased in all subjects, with a peak in both systolic and diastolic velocity 20 min after drug administration. At that time systolic velocity increased by 35% and diastolic velocity by 50% in comparison to basal values. In contrast with Xenon 133 technique which gives one measurement only for each investigation, TCD allows a continuous monitoring of haemodynamic change following AZ infusion. MCA diastolic velocity at rest was inversely related to age (r = -.804, p < 0.01); baseline diastolic velocity was inversely related to the maximum percentage increment (r = -.745 p < .05). No change in blood pressure and heart rate was observed under experimental conditions. These results, confirm the usefulness of the AZ test in the evaluation of cerebrovascular reactivity and strongly support the use of TCD technique applied to AZ in order to investigate cerebrovascular haemodynamics in normal healthy subjects and in patients at risk of cerebrovascular insufficiency.
乙酰唑胺（AZ）是一种碳酸酐酶的选择性抑制剂，经静脉注射氙133技术证实可增加脑血流量（CBF）。在本研究中，由于多项报告表明脑血流速度与CBF密切相关，因此通过经颅多普勒（TCD）在10名正常受试者的大脑中动脉（MCA）内评估了对AZ的脑血管反应性。注射1克AZ后，所有受试者的血流速度均显著增加，给药后20分钟收缩期和舒张期速度均达到峰值。此时，与基础值相比，收缩期速度增加了35%，舒张期速度增加了50%。与氙133技术每次检查只能进行一次测量不同，TCD允许在输注AZ后连续监测血流动力学变化。静息时MCA舒张期速度与年龄呈负相关（r = -0.804，p < 0.01）；基线舒张期速度与最大百分比增量呈负相关（r = -0.745，p < 0.05）。在实验条件下未观察到血压和心率的变化。这些结果证实了AZ试验在评估脑血管反应性方面的有用性，并有力地支持了将TCD技术应用于AZ，以研究正常健康受试者和有脑血管供血不足风险患者的脑血管血流动力学。
