Mohama R E, Joyner W L, Gilmore J P
Microcirc Endothelium Lymphatics. 1984 Aug;1(4):397-413.
Experiments were carried out to determine the relative sensitivity of hamster cheek pouch vessels to arginine vasopressin (AVP) and angiotensin II (AII). Hamsters were anesthetized with pentobarbital sodium (6 mg/100 g, ip), a plastic chamber inserted into the cheek pouch and the membrane exposed. The membrane was suffused continuously with bicarbonate-buffered Ringer's solution at 36 degrees C while constantly monitoring blood pressure. After stabilization (30 min) of the membrane, arterioles (30-80 microM diam) were selected for application of AVP or AII in a random fashion. The peptides were applied to the vessels through a micropipette (10-15 mM tip diam) over two minutes using a pump. Total volume delivered was always 20 microliters irrespective of the total amount of peptide (10(0)-10(-4) ng) applied. Vessel diameter was monitored continuously with a shearing device before, during and after the administration of the peptide. The following results were obtained tachyphylaxis was noted to AII but to AVP; the dose response curve for AVP was shifted to the left of that for AII with the threshold dose for AII one hundred times more than that of AVP and AVP had little effect on venules whereas AII produced venoconstriction. These results indicate that AVP is a more potent vasoconstrictor than AII, whereas AII is a more potent venoconstrictor.
开展实验以确定仓鼠颊囊血管对精氨酸加压素（AVP）和血管紧张素II（AII）的相对敏感性。用戊巴比妥钠（6毫克/100克，腹腔注射）麻醉仓鼠，将一个塑料腔插入颊囊并暴露其膜。在36摄氏度下，用碳酸氢盐缓冲的林格氏液持续灌注该膜，同时持续监测血压。在膜稳定（30分钟）后，随机选择直径为30 - 80微米的小动脉用于施加AVP或AII。使用泵在两分钟内通过微量移液器（尖端直径10 - 15毫米）将肽施加到血管上。无论施加的肽总量（10⁰ - 10⁻⁴纳克）如何，输送的总体积始终为20微升。在肽给药前、给药期间和给药后，用剪切装置连续监测血管直径。获得了以下结果：观察到对AII有快速耐受性，但对AVP没有；AVP的剂量反应曲线比AII的向左偏移，AII的阈值剂量比AVP高一百倍，并且AVP对小静脉几乎没有影响，而AII会引起静脉收缩。这些结果表明，AVP是比AII更强效的血管收缩剂，而AII是更强效的静脉收缩剂。
