Stroke treatment in rats
Functional impairment has been attained by a transient (tMCAo) or a permanent (pMCAo) occlusion resulting in neurological deficits and long-term or permanent motor dysfunction.á The consequences of either mode of occlusion has been assessed in terms of infarct size, and neurological and cognitive improvement using verified scoring systems.
Evaluation of efficacy parameters on either tMCAo or pMCAo rats which received SPG stimulation showed an increase in Cerebral Blood Flow, a decrease in infarct volume and improvement in neurological function as measured by a series of behavioral tests detailed in the literature. MR spectroscopy studies also indicated better infarct metabolic recovery following SPG stimulation.
Improvement of the above parameters can be shown after extended delays (up to 24 hours) following occlusion. Beneficial effects can be observed up to 4 weeks after the MCA occlusion, and may be attributed to either the long-term influence of SPG stimulation, or to a long-term rehabilitation process.
Based on the data in which SPG stimulation was applied 24 hours after the onset of stroke, it is hypothesized that SPG stimulation may expand the therapeutic window from the current 3 hours (for treatment with tPA) to 24 hours for patients with ischemic stroke.