Leonetti G
Istituto Scientifico Ospedale San Luca, Milano, Italy.
J Cardiovasc Pharmacol. 1994;24 Suppl A:S25-9.
As direct vasodilating agents, calcium antagonists cause a significant reduction in total peripheral resistance in hypertensive patients. However, calcium antagonists differ significantly from direct vasodilating agents in their effects on sodium and water balance. Whereas direct vasodilating agents often cause sodium and water retention and the development of "pseudotolerance," calcium antagonists have no effect or cause a short-lasting natriuretic and diuretic effect. In our experience, dihydropyridine calcium antagonists with short-lasting and rapid onset of antihypertensive effect cause a significant rise in sodium and water excretion during the first and second days of oral administration. In contrast, calcium antagonists with a slower and longer-lasting blood pressure reduction cause a nonsignificant trend in sodium and water excretion with no signs or symptoms of retention. Finally, the antihypertensive effect of nifedipine is present in sodium-depleted and sodium-repleted patients. Calcium antagonists can increase sodium and water retention, although the antihypertensive effect is unrelated to their diuretic and natriuretic actions.
作为直接血管扩张剂，钙拮抗剂可使高血压患者的总外周阻力显著降低。然而，钙拮抗剂在对钠和水平衡的影响方面与直接血管扩张剂有显著差异。直接血管扩张剂常导致钠和水潴留以及“假性耐受”的发生，而钙拮抗剂则无此作用或仅引起短暂的利钠和利尿作用。根据我们的经验，具有短效和快速起效降压作用的二氢吡啶类钙拮抗剂在口服给药的第一天和第二天可使钠和水排泄显著增加。相比之下，降压作用较慢且持续时间较长的钙拮抗剂可使钠和水排泄呈不显著的趋势，且无潴留的体征或症状。最后，硝苯地平的降压作用在低钠和高钠患者中均存在。钙拮抗剂可增加钠和水潴留，尽管其降压作用与其利尿和利钠作用无关。
