Fujii K, Heistad D D, Faraci F M
Department of Internal Medicine, Veterans Administration Medical Center, Iowa City, Iowa.
Am J Physiol. 1990 Jun;258(6 Pt 2):H1829-34. doi: 10.1152/ajpheart.1990.258.6.H1829.
Vasomotion is a rhythmic change in vascular caliber that has been described in vivo mainly in peripheral arterioles. In this study, we have characterized vasomotion in a large artery of the brain in vivo. In anesthetized rats, spontaneous vasomotion was observed in 38 of 47 basilar arteries visualized through a cranial window. Base-line arterial diameter was 259 +/- 9 (means +/- SE) microns. Under control conditions, the frequency of vasomotion was 4.8 +/- 0.2 cycles/min, and the amplitude was 19 +/- 2% of the mean diameter. Vasomotion usually occurred simultaneously along the entire length of the vessel, but in some arteries it propagated in either direction. Moderate hypertension (phenylephrine) or vasoconstriction induced by topical application of serotonin, vasopressin, or the thromboxane analogue U 46619 increased the frequency of vasomotion. Moderate hypotension or vasodilation induced by nitroglycerin, adenosine, or acetylcholine decreased the frequency. Marked hypertension, hypotension, or vasodilatation abolished vasomotion. Thus vasomotion of the basilar artery in vivo 1) is common and of relatively large amplitude, 2) does not seem to be driven by a single pacemaker, and 3) is dependent on vessel diameter or vasomotor tone.
血管运动是血管口径的一种节律性变化，主要在活体的外周小动脉中被描述。在本研究中，我们已对活体脑大动脉中的血管运动进行了特征描述。在麻醉大鼠中，通过颅窗观察到47条基底动脉中有38条存在自发性血管运动。基线动脉直径为259±9（平均值±标准误）微米。在对照条件下，血管运动的频率为4.8±0.2次/分钟，幅度为平均直径的19±2%。血管运动通常在血管的整个长度上同时发生，但在一些动脉中它会向任一方向传播。中度高血压（去氧肾上腺素）或局部应用5-羟色胺、血管加压素或血栓烷类似物U 46619诱导的血管收缩增加了血管运动的频率。硝酸甘油、腺苷或乙酰胆碱诱导的中度低血压或血管舒张降低了频率。显著的高血压、低血压或血管舒张会消除血管运动。因此，活体基底动脉的血管运动1）常见且幅度相对较大，2）似乎不是由单个起搏器驱动的，3）取决于血管直径或血管运动张力。
