Small animal model for investigation of subarachnoid hemorrhage and cerebral vasospasm.

A method for induction of subarachnoid hemorrhage (SAH) in a rat model is described. Resolution of the hemorrhage was documented photographically and microscopically at intervals from 1 hr to 8 days. Photographs indicated that most of the hemorrhage was resorbed within 3 days, an observation confirmed microscopically by the amount of red blood cells in the subarachnoid space. Significant cerebral vasospasm was documented within the first 2 days after the induction of hemorrhage with the basilar artery returning to baseline values at an average of 3 days followed by moderate dilatation at 5 to 8 days. The suitability of the rat as an animal model for further investigation of subarachnoid hemorrhage is discussed.