Stroke is a leading cause of death in North America, and patients who survive a stroke usually suffer from cognitive impairment. As of yet, there is no treatment for cognitive deficits resulting from stroke. Samson et al. investigate the mechanism of action of erythropoietin (using an analog, Darbepoetin alfa) on spatial working memory performance in rats with pre-existing cognitive deficits due to cerebral ischemia. The authors show that Darbepoetin alfa-induced cognitive improvement in rats subjected to 4-vessel occlusion (4-VO) was associated with increased levels of nitric oxide metabolites in the hippocampus. By use of the nitric-oxide synthase inhibitor NG-nitro-l-nitro-arginine methyl ester (l-NAME), they prevented both an increase in nitric oxide metabolite formation and cognitive improvement, suggesting that erythropoietins may improve cognition performance in stroke patients by activating nitric-oxide synthase signaling pathways.
See article at J Pharmacol Exp Ther 2010, 333:437–444. (8936)
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