Webb A C, Ebenezer I S, Burns B D
Regul Pept. 1987 May;17(5):257-67. doi: 10.1016/0167-0115(87)90283-7.
A videocamera and a dissecting microscope have been used to record the effects of arginine-8 vasopressin (AVP) upon pial blood vessels in anaesthetised rats. Topical application of AVP caused a contraction of pial arteries, but had no measureable effect upon the diameter of veins. The smallest concentration of AVP that was effective in contracting arteries was 10(-7) mU/microliter. Stronger solutions (10(-5) to 2.0 mU/microliter) produced approximately the same (45%) reduction of external diameter. Contraction was maximal 0.25-1.0 min after application of the hormone, had almost recovered (10% contraction) after 10 min, and showed complete recovery by 30 min. Concentrations of AVP that were greater than 10(-3) mU/microliter produced tachyphylaxis, so that a second application of AVP 30 min later had considerably less effect. Concentrations less than 10(-3) mU/microliter produced no detectable tachyphylaxis. These results suggest that blood flow to the normal cerebral cortex may be partly under tonic control by the local concentration of AVP.
利用一台摄像机和一台解剖显微镜记录了精氨酸 -8 加压素（AVP）对麻醉大鼠软脑膜血管的影响。局部应用 AVP 可使软脑膜动脉收缩，但对静脉直径没有可测量的影响。有效收缩动脉的最小 AVP 浓度为 10（-7）mU/微升。更强的溶液（10（-5）至 2.0 mU/微升）使外径减少了约相同的幅度（45%）。应用该激素后 0.25 - 1.0 分钟收缩达到最大，10 分钟后几乎恢复（10%收缩），30 分钟时完全恢复。大于 10（-3）mU/微升的 AVP 浓度会产生快速耐受性，因此 30 分钟后再次应用 AVP 效果明显减弱。小于 10（-3）mU/微升的浓度未产生可检测到的快速耐受性。这些结果表明，正常大脑皮层的血流可能部分受局部 AVP 浓度的紧张性控制。
