Behavioral deficits following experimental subarachnoid hemorrhage in the rat

To characterize some of the short-term and long-term functional consequences of subarachnoid hemorrhage (SAH) in rats, we employed a battery of well-characterized tests for assessment of acute and chronic behavioral and neurologic performances. Three groups of 10 rats (blood injected, mock CSF injected and sham-operated controls) were studied. During the acute stage, simple nonpostural somatomotor reflexes (pinna and corneal reflexes), simple postural responses (paw flexion, tail flexion, and head support), startle response, and postural functions (righting reflex) did not differ significantly between the experimental groups. Assessments of body weight, beam walking ability, and beam balancing revealed significant disturbances in blood-injected rats. This work demonstrates that this single-hemorrhage rodent model of SAH is associated with the induction of enduring neurologic and behavioral deficits. Because of the significant interspecies difference, a direct extrapolation of our results to humans may not be appropriate. However, we suggest that the observed behavioral and neurologic changes may parallel those seen in humans after SAH. Results reported here further confirm the rat model of SAH as a viable laboratory instrument for the study of the pathophysiology of SAH and provide normative values for the evaluation of new treatment modalities.