Mzail A H, Noble A R
Clin Exp Pharmacol Physiol. 1986 Mar;13(3):187-94. doi: 10.1111/j.1440-1681.1986.tb00336.x.
Regulation of plasma active and inactive renin was investigated using conscious sheep with indwelling artery, vein and bladder catheters. Control and experimental studies were carried out in the same animals on different days. The calcium antagonist drug verapamil was given as an initial bolus injection (0.5 mg/kg) followed by a continuous infusion (0.1 mg/kg per h) over a 2.5 h period. Plasma active and inactive renin changed in parallel. Both were significantly increased within 15 min of the initial drug dose and both attained a peak increase after 45 min. Thereafter, the two forms of renin returned to basal levels despite continued infusion of the drug. Effective renal plasma flow (CPAH) was also transiently increased by verapamil and followed a similar time course to changes in plasma active and inactive renin concentration. Arterial blood pressure, however, remained suppressed by verapamil for the duration of the study. Verapamil did not alter urine flow or sodium and potassium excretion rates. These results are discussed in relation to the possible link between intrarenal haemodynamics and renin secretion in conscious and in anaesthetized animals and also in relation to the concept that variation in the relative amounts of active and inactive renin secreted in differing physiological situations represents a mechanism for regulating the renin-angiotensin system.
利用留置动脉、静脉和膀胱导管的清醒绵羊，研究了血浆活性肾素和非活性肾素的调节情况。对照研究和实验研究在同一天对同一批动物进行。钙拮抗剂药物维拉帕米先给予一次推注（0.5毫克/千克），然后在2.5小时内持续输注（每小时0.1毫克/千克）。血浆活性肾素和非活性肾素呈平行变化。在给予初始药物剂量后15分钟内，两者均显著增加，且在45分钟后均达到峰值增加。此后，尽管持续输注药物，两种形式的肾素均恢复至基础水平。维拉帕米也使有效肾血浆流量（CPAH）短暂增加，且其时间进程与血浆活性肾素和非活性肾素浓度的变化相似。然而，在研究期间，维拉帕米持续抑制动脉血压。维拉帕米未改变尿流量或钠、钾排泄率。结合清醒和麻醉动物肾内血流动力学与肾素分泌之间可能的联系，以及在不同生理情况下分泌的活性肾素和非活性肾素相对量的变化代表一种调节肾素-血管紧张素系统的机制这一概念，对这些结果进行了讨论。
