¹Department of Neurobiology, Neuroscience Institute, Morehouse School of Medicine, Atlanta, Georgia, USA

Correspondence: Dr S Namura, Department of Neurobiology, Neuroscience Institute, Morehouse School of Medicine, 720 Westview Dr. SW, Atlanta, GA 30310, USA. E-mail: snamura@msm.edu

Received 1 May 2009; Revised 15 July 2009; Accepted 8 August 2009; Published online 2 September 2009.

Abstract

Fibrates, one group of peroxisome proliferator-activated receptor (PPAR) activators, are lipid lowering drugs. Fibrates have been shown to attenuate brain tissue injury after focal cerebral ischemia. In this study, we investigated the impact of fenofibrate on cerebral blood flow (CBF) in male wild type and PPAR-null mice. Animals were treated for 7 days with fenofibrate and subjected to 2 h of filamentous middle cerebral artery occlusion and reperfusion under isoflurane anesthesia. Cortical surface CBF was measured by laser speckle imaging. Regional CBF (rCBF) in nonischemic animals was measured by ¹⁴C-iodoantipyrine autoradiography. Fenofibrate did not affect rCBF and mean arterial blood pressure in nonischemic animals. In ischemic animals, laser speckle imaging showed delayed expansions of ischemic area, which was attenuated by fenofibrate. Fenofibrate also enhanced CBF recovery after reperfusion. However, such effects of fenofibrate on CBF in the ischemic brain were not observed in PPAR-null mice. These findings show that fenofibrate improves CBF in the ischemic hemisphere. Moreover, fenofibrate requires PPAR expression for the cerebrovascular protective effects in the ischemic brain.