Hundley W G, Renaldo G J, Levasseur J E, Kontos H A
Department of Medicine, Medical College of Virginia, Richmond 23298.
Am J Physiol. 1988 Jan;254(1 Pt 2):H67-71. doi: 10.1152/ajpheart.1988.254.1.H67.
Cerebral arterioles of unanesthetized rabbits equipped with chronically implanted cranial windows exhibited spontaneous rhythmic variation in vessel caliber characteristic of vasomotion. This variation was noted in all examined vessels. The vasomotion was independent of arterial blood pressure or respiration. The average frequency was 0.74 cycles/min and was independent of vessel size. The mean amplitude of the oscillations had a statistically significant inverse relationship to vessel diameter (r = 0.69). Vasodilation induced by arterial hypercapnia, topical adenosine, or topical acetylcholine had no significant effect on the frequency or amplitude of vasomotion. Anesthesia significantly reduced the frequency in arterioles of all sizes and markedly reduced amplitude in large arterioles. Topical verapamil resulted in a statistically significant reduction in frequency and in peak amplitude. Variations in vessel diameter occurred simultaneously in arterioles and their companion venules. We conclude that the cerebral microcirculation displays active vasomotion, which is significantly depressed by anesthesia or topical verapamil. The results also suggest that vasomotion is probably controlled by local factors.
在配备了长期植入颅骨视窗的未麻醉家兔的脑小动脉中，观察到血管口径呈现出自发性节律性变化，这是血管运动的特征。在所有检查的血管中均发现了这种变化。血管运动与动脉血压或呼吸无关。平均频率为0.74次/分钟，且与血管大小无关。振荡的平均幅度与血管直径呈统计学上显著的负相关（r = 0.69）。动脉血二氧化碳分压升高、局部应用腺苷或局部应用乙酰胆碱所诱导的血管舒张对血管运动的频率或幅度没有显著影响。麻醉显著降低了所有大小小动脉的频率，并显著降低了大动脉的幅度。局部应用维拉帕米导致频率和峰值幅度在统计学上显著降低。小动脉及其伴行小静脉的血管直径变化同时发生。我们得出结论，脑微循环表现出活跃的血管运动，麻醉或局部应用维拉帕米会使其显著受到抑制。结果还表明，血管运动可能受局部因素控制。
