Cytoprotective therapies in stroke.

Cytoprotective strategies continue to be intensively investigated in animal models of focal and global ischaemia. New classes of pharmacological agents are still being identified which are effective in reducing the severity of ischaemic damage when administered shortly after the ischaemia. Many such agents reduce neuronal activity and decrease sodium and calcium entry. Later stages in excitotoxic processes can, however, be affected by nitric oxide synthase inhibitors or free-radical scavengers. Different types of compound have different relative potencies against reversible or permanent focal ischaemia, and mild or complete transient ischaemia. Positive results in clinical trials remain elusive. Trial design is improving; the emphasis is on early initiation of therapy and refined criteria for admission and final evaluation. The results of several current trials are eagerly awaited.