Calcium antagonists and renal protection.

Aim: To review the renal benefits of calcium antagonists.
Methods: Review of published 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 preservation. In three well defined clinical situations, the use of calcium antagonists has proved to be of value. First, in acute renal failure we and others have shown that the administration of dihydropyridine or diltiazem can, by preventing an intracellular calcium overload, avoid the renal damage induced by the use of a radiographic contrast agent. Second, in chronic renal failure, the administration of a calcium antagonist has been shown to be safe and at least similar in efficacy to other commonly used antihypertensive drug classes. Third, in renal transplant patients, calcium antagonists have been shown to prevent both acute and chronic cyclosporin nephrotoxicity. Calcium antagonists have a clear advantage in the case of acute toxicity because they allow faster renal function recovery and a shorter hospitalization time. The mechanisms by which this class reduces cyclosporin toxicity may be related to a reduction in the calcium influx into cells during ischaemic and reperfusion periods, which would reduce the generation of oxygen-free radicals and perhaps reduce thromboxane production.
Conclusions: Calcium antagonists have potential renal protective effects that favour their use in many clinical situations where renal function is impaired.