Recombinant Fv-Hsp70 protein mediates neuroprotection after focal cerebral ischemia in rats.

BACKGROUND AND PURPOSE This study investigated the effects of intravenous recombinant Fv-Hsp70 protein on infarction volume and behavior after experimental ischemic stroke. METHODS Focal cerebral ischemia was produced by occluding the middle cerebral artery using the intraluminal suture technique. Rats subjected to 2 hours of focal ischemia were allowed to survive 24 hours. At 2(1/4) hours and 3 hours after onset of ischemia, Fv-Hsp70 recombinant protein (0.5 mg/kg) or saline was injected through the tail vein. Sensorimotor function and infarction volume were assessed at 24 hours after ischemia. RESULTS Administration of Fv-Hsp70 after focal cerebral ischemia significantly decreased infarct volume by 68% and significantly improved sensorimotor function compared with the saline-treated control group. Western blots showed Fv-Hsp70 in ischemic but not in control brain; and Fv-Hsp70 suppressed endogenous Hsp70. CONCLUSIONS Fv-Hsp70 protected the ischemic brain in this experimental stroke model.