Abstract
Modern neuroimaging detects more frequently cerebral white matter lesions. These lesions, which are highly observed in old people and/or patients with cerebrovasucular diseases, are caused by chronic cerebral hypoperfusion and associated with cognitive disturbance. In addition, it has been recognized that preventing white matter damage is quite important to ameliorate ischemic neuronal damage. But the mechanisms of white matter damage and the drug sensitivity of white matter are quite different from those of grey matter. We investigated effects of hypocapnia induced by hyperventilation on white matter lesions using a rat model of chronic cerebral hypoperfusion. Hypocapnia exclusively aggravated white matter lesions in the caudoputamen, which is associated with cognition and working memory. The lesions were significantly alleviated by ketamine, an N-methyl-D-aspartate receptor antagonist. Our results may imply postoperative brain dysfunction, such as delirium, in old people or patients with cerebrovascular diseases may be due, at least partly, to the aggravation of white matter lesions in the caudoputamen.
