Bøtker H E, Jensen H K, Krusell L R, Sørensen E V
Department of Medicine and Cardiology, Aarhus County and University Hospital, Denmark.
Cardiovasc Drugs Ther. 1993 Feb;7(1):111-6. doi: 10.1007/BF00878318.
The acute renal effects of xamoterol, a partial beta 1-agonist, were studied in 12 patients with congestive heart failure (NYHA II-III) in stable condition on diuretic therapy for at least 6 weeks. Each patient was given a single intravenous infusion of xamoterol (0.2 mg/kg) or placebo in random order 2 weeks apart. Using constant infusion and lithium clearance techniques, clearance and excretion measurements were made in the supine position at 30- to 60-min intervals before, during, and up to 6 hours after infusion. Blood pressure, heart rate, renal plasma flow, glomerular filtration rate, and urinary flow rate remained unchanged, but xamoterol lowered sodium excretion by 30% (p < 0.05). The decrease started 120 minutes after infusion. Proximal reabsorption of sodium increased after xamoterol infusion, whereas plasma values of aldosterone and angiotensin II were unaffected. It is concluded that the acute renal effects of xamoterol imply an impaired sodium excretion determined by the tubular actions of the drug. The present results suggest that xamoterol may aggravate one of the important abnormalities intrinsic to the pathology of congestive heart failure. These findings are in contrast to the beneficial effects of xamoterol demonstrated in many clinical trials where xamoterol was given orally for a longer period.
对12例病情稳定、接受利尿剂治疗至少6周的充血性心力衰竭（纽约心脏协会II - III级）患者，研究了部分β1激动剂扎莫特罗的急性肾脏效应。每位患者随机顺序接受单次静脉输注扎莫特罗（0.2mg/kg）或安慰剂，间隔2周。采用持续输注和锂清除技术，在输注前、输注期间及输注后长达6小时内，每隔30至60分钟让患者仰卧位进行清除率和排泄量测量。血压、心率、肾血浆流量、肾小球滤过率和尿流率保持不变，但扎莫特罗使钠排泄降低了30%（p < 0.05）。这种降低在输注后120分钟开始。扎莫特罗输注后近端钠重吸收增加，而醛固酮和血管紧张素II的血浆值未受影响。结论是，扎莫特罗的急性肾脏效应意味着药物的肾小管作用导致钠排泄受损。目前的结果表明，扎莫特罗可能会加重充血性心力衰竭病理中固有的重要异常之一。这些发现与许多临床试验中口服扎莫特罗较长时间所显示的有益效果形成对比。
