Kimura M, Dietrich H H, Huxley V H, Reichner D R, Dacey R G
Department of Neurosurgery, Washington University School of Medicine, St. Louis, Missouri 63110.
Am J Physiol. 1993 Jun;264(6 Pt 2):H1788-97. doi: 10.1152/ajpheart.1993.264.6.H1788.
We have developed a new method for quantification of arteriolar hydraulic conductivity (Lp) from isolated rat brain vessels. The volume flux of water per unit surface area across the arteriole wall (Jv/S) was assessed from measurements of silicon oil drop movement within an occluded vessel at two to three pressures (between 20 and 70 mmHg); the Lp was derived from the slope of the relationship between Jv/S and applied pressure. Lp was measured in isolated cerebral arterioles 1) at room temperature (22 degrees C) without spontaneous vessel tone (control Lp; n = 11), 2) at room temperature with 10(-4) M adenosine (n = 5), and 3) at 37 degrees C with vessels dilated submaximally with 10(-4) M adenosine (n = 6). Lp at 22 degrees C without adenosine was 13.2 +/- 4.2 x 10(-9) (+/- SE) cm.s-1.cmH2O-1 for all vessels studied. Lp values ranged from 1.2 to 44.1 x 10(-9) cm.s-1.cmH2O-1 with a median value that was 5.9 x 10(-9) cm.s-1.cmH2O-1. Lp increased significantly (on average, 2.6-fold) with adenosine at 37 degrees C but not with adenosine at 22 degrees C. Control Lp bore no relationship to either the development of spontaneous tone or the diameter response to pH change, two recognized indicators of vessel viability.
我们开发了一种新方法，用于从分离的大鼠脑血管中定量测定小动脉水力传导率（Lp）。通过在两到三个压力（20至70 mmHg之间）下测量封闭血管内硅油滴的移动，评估单位表面积水通过小动脉壁的体积通量（Jv/S）；Lp由Jv/S与施加压力之间关系的斜率得出。在以下条件下测量分离的脑小动脉的Lp：1）室温（22℃）下无自发血管张力（对照Lp；n = 11），2）室温下加入10⁻⁴ M腺苷（n = 5），3）37℃下用10⁻⁴ M腺苷使血管次最大程度扩张（n = 6）。对于所有研究的血管，22℃无腺苷时的Lp为13.2±4.2×10⁻⁹（±SE）cm·s⁻¹·cmH₂O⁻¹。Lp值范围为1.2至44.1×10⁻⁹ cm·s⁻¹·cmH₂O⁻¹，中位数为5.9×10⁻⁹ cm·s⁻¹·cmH₂O⁻¹。37℃时腺苷使Lp显著增加（平均增加2.6倍），但22℃时腺苷未使其增加。对照Lp与自发张力的发展或对pH变化的直径反应（两种公认的血管活力指标）均无关系。
