Regional Cerebral Blood Flow Autoregulation in a Silicone Embolus Model of Focal Brain Ischemia as Assessed by Multichannel Laser Doppler Flowmetry

The overall goal of this research is to better understand the mechanisms underlying the dysfunction of cerebral blood flow (CBF) autoregulation after an ischemic insult. Towards this purpose, a rat focal cerebral ischemia model has been developed that does not require craniotomy and would be compatible with continuous monitoring of regional CBF using multichannel laser Doppler flowmetry (LDF) throughout the ischemic period. The most common models of focal ischemia in rodents have utilized either ligation, coagulation or intraluminal obstruction of the middle cerebral artery.18,2,3,4,10 These approaches involve craniotomy or are performed in the supine position which is inconvenient for multichannel LDF recording. It is important to continuously monitor regional CBF in multiple brain areas because the pattern and the time course of CBF changes (hyperemia versus hypoperfusion) may be different in various brain regions and may thereby influence the extent and severity of eventual neuronal injury.