心脏选择性和非选择性β-肾上腺素能受体阻滞剂对人体低钾血症及对肾上腺髓质激素心血管反应的影响。

The effects of cardioselective and non-selective beta-adrenoceptor blockade on the hypokalaemic and cardiovascular responses to adrenomedullary hormones in man.

作者信息

Struthers A D, Reid J L, Whitesmith R, Rodger J C

出版信息

Clin Sci (Lond). 1983 Aug;65(2):143-7. doi: 10.1042/cs0650143.

Abstract

Adrenaline was infused intravenously in nine normal volunteers to plasma concentrations similar to those found after myocardial infarction. This study was undertaken on three occasions after 5 days' treatment with placebo or the beta-adrenoceptor antagonists, atenolol or timolol. Adrenaline increased the systolic pressure by 11 mmHg, decreased the diastolic pressure by 14 mmHg, and increased the heart rate by 7 beats/min. These changes were prevented by atenolol. However, after timolol the diastolic pressure rose (+19 mmHg) and heart rate fell (-8 beats/min). Adrenaline caused the corrected QT interval (QTc) to lengthen (0.36 +/- 0.02 s to 0.41 +/- 0.06 s). No significant changes were found in the QTc when subjects were pretreated with atenolol or timolol. The serum potassium fell from 4.06 to 3.22 mmol/l after adrenaline. Serum potassium fell to a lesser extent to 3.67 mmol/l after atenolol and actually increased to 4.25 mmol/l after timolol. Adrenaline-mediated hypokalaemia appears to result from the stimulation of a beta 2-adrenoceptor linked to membrane Na+/K+-ATPase causing potassium influx.

摘要

对9名正常志愿者静脉输注肾上腺素，使其血浆浓度达到与心肌梗死后相似的水平。本研究在给予安慰剂或β-肾上腺素受体拮抗剂阿替洛尔或噻吗洛尔治疗5天后进行了3次。肾上腺素使收缩压升高11 mmHg，舒张压降低14 mmHg，心率增加7次/分钟。这些变化被阿替洛尔阻止。然而，在使用噻吗洛尔后，舒张压升高（+19 mmHg），心率下降（-8次/分钟）。肾上腺素使校正QT间期（QTc）延长（从0.36±0.02秒延长至0.41±0.06秒）。当受试者用阿替洛尔或噻吗洛尔预处理时，QTc未发现显著变化。肾上腺素作用后血清钾从4.06 mmol/L降至3.22 mmol/L。阿替洛尔作用后血清钾下降幅度较小，降至3.67 mmol/L，而噻吗洛尔作用后血清钾实际上升至4.25 mmol/L。肾上腺素介导的低钾血症似乎是由于与膜Na+/K+-ATP酶相连的β2-肾上腺素受体受到刺激，导致钾内流所致。