CALCIUM-ANTAGONISTS AND RENAL PROTECTION

Aim: To review the renal benefits of calcium antagonists. Review of pu blished studies. Results: Both experimental and clinical studies have indicated that, apart from being highly potent antihypertensive agents , calcium antagonists may also provide tissue protection and preservat ion. In three well defined clinical situations, the use of calcium ant agonists has proved to be of value. First, in acute renal failure we a nd others have shown that the administration of dihydropyridine or dil tiazem can, by preventing an intracellular calcium overload, avoid the renal damage induced by the use of a radiographic contrast agent. Sec ond, in chronic renal failure, the administration of a calcium antagon ist has been shown to be safe and at least similar in efficacy to othe r commonly used antihypertensive drug classes. Third, in renal transpl ant patients, calcium antagonists have been shown to prevent both acut e and chronic cyclosporin nephrotoxicity. Calcium antagonists have a c lear advantage in the case of acute toxicity because they allow faster renal function recovery and a shorter hospitalization time. The mecha nisms by which this class reduces cyclosporin toxicity may be related to a reduction in the calcium influx into cells during ischaemic and r eperfusion periods, which would reduce the generation of oxygen-free r adicals and perhaps reduce thromboxane production. Conclusions. Calciu m antagonists have potential renal protective effects that favour thei r use in many clinical situations where renal function is impaired.