KB-R7943, an inhibitor of the reverse Na+/Ca2+ exchanger, does not modify secondary pathology in the thalamus following focal cerebral stroke in rats

Remote areas connected to cortical infarcts, such as the thalamus, are affected by stroke due to delayed retrograde degeneration of afferent connections. This is temporally associated with the accumulation of β-amyloid (Aβ) and calcium. Here we tested a hypothesis that prevention of excessive Ca2+ influx into the axoplasm via the reverse Na+/Ca2+ exchanger (NCX) would provide axonal protection and eventually lessen the Aβ and calcium load in the thalamus. We found that chronic treatment with a specific inhibitor of the reverse NCX, KB-R7943 (30 mg/kg once daily, 27 days) after middle cerebral artery occlusion did not prevent atypical secondary pathology in the thalamus or improve functional outcome. The present data do not support a role for reverse NCX activity in the complex pathology within the thalamus after cerebral ischemia.