单用噻嗪类利尿剂治疗原发性高血压时,增加其剂量,降压效应几无增强,但引起代谢紊乱的作用却增加了,例如发生低血钾症等。这主要是由于利尿剂促进了肾素的释放,随之使血管紧张素Ⅱ的血浓度升高,因此尽管增加利尿药的剂量,钠和水的排泄增加,而血压不再下降。β-阻滞剂可通过抑制交感系统而使肾素分泌减少,使循环中血管紧张素Ⅱ的浓度下降大约一半。这可能是它与利尿剂合用呈现相加作用的部分原因。然而,β-阻滞剂仅仅是抑制了通过交感 Thiazide diuretics alone treatment of essential hypertension, increasing its dose, antihypertensive effect few enhancers, but the role of metabolic disorders have increased, such as the occurrence of hypokalemia. This is mainly because diuretics promote the release of renin, which in turn increases the blood concentration of angiotensin II, so that despite increased doses of diuretics, excretion of sodium and water increases and blood pressure no longer decreases. Beta-blockers reduce renin secretion by inhibiting the sympathetic system, reducing the concentration of circulating angiotensin II by about half. This may be part of the reason for its additive effect with diuretics. However, beta-blockers simply inhibit sympathetic cross-talk