Dimethyl sulfoxide (DMSO) and glycerol, hydroxyl radical scavengers, impair platelet aggregation within and eliminate the accompanying vasodilation of, injured mouse pial arterioles.

The hydroxyl radical scavengers dimethyl sulfoxide (DMSO) and glycerol were effective inhibitors of platelet aggregation in an in vivo mouse model of pial arteriolar injury. Aggregability was expressed in terms of the time required for a noxious stimulus (light + dye) to initiate aggregation. These drugs, given 1 hour before the injury, also eliminated the dilation which accompanied the damage. The same drugs failed to influence the constriction which accompanied an identical injury to mouse mesenteric arterioles, but again impaired platelet aggregation in the damaged mesenteric vessel. The data support the concept recently introduced by others, that, in the brain, hydroxyl radicals may mediate vascular damage and/or dilation accompanying the damage. The data also support the concept platelet aggregation may be stimulated, directly or indirectly, by hydroxyl radical. The effects of DMSO and glycerol in this study, irrespective of the molecular basis for the effects, may be relevant to the reported therapeutic benefit of these agents in cerebrovascular disease.