Abstract 2981: Neuroprotective Effect Of Acute Ethanol Administration In Rat With Transient Cerebral Ischemia
Background and Purpose _ Despite a focus on the pathological effects of alcohol abuse, numerous studies published over the past several decades also demonstrate beneficial effects of light-to-moderate consumption of alcoholic beverages. Recent studies have demonstrated that elevated serum ethanol levels are associated with increased survival in patients with traumatic brain injury (TBI), suggesting that an acute exposure to alcohol exerts a neuroprotective effect. In a rat model of transient cerebral ischemia, we identified administration of ethanol as a possible treatment for acute ischemic stroke.
Methods _Sprague-Dawley rats were subjected to middle cerebral artery occlusion (MCAO) for two hours. Five sets of experiments were conducted: 1) to determine the dose-response effect of ethanol (0.5, 1.0 and 1.5g/kg) on brain infarction and functional outcome; 2) to determine whether combining ethanol (1.5g/kg) and hypothermia produces synergistic neuroprotection; 3) to determine the therapeutic windows of opportunity for ethanol in stroke; to test whether ethanol promotes intracerebral hemorrhage (ICH) in hemorrhagic or ischemic stroke, or after administration of thrombolytics in ischemic stroke; and 5) to test the affect of ethanol on HIF-1α protein expression.
Results —Ethanol at 1.5 g/kg, which produce blood levels (89mg/dL) within the legally intoxicated range for driving (80-100 g/dL), most effectively reduced infarct volume and behavioral dysfunction when administered at 2, 3 or 4 hours after MCAO. We find that ethanol and moderate hypothermia (32-34 °C) exert neuroprotective effects of similar magnitude at both the lesion volume and functional levels, but do not exert a synergistic effect in this model. Ethanol did not promote cerebral hemorrhage in hemorrhagic or ischemic stroke in combination with recombinant tissue plasminogen activator (rt-PA) or urokinase (UK). Up-regulation of HIF-1α protein levels was enhanced by ethanol, in association with reduced brain infarct volume and improved functional recovery in rats subjected to stroke using the same dose (1.5 g/kg).
Conclusions —Ethanol exerts a strong neuroprotective effect when administered up to 4 hours after ischemia, and does not promote ICH when used with thrombolytics. Ethanol is a potential neuroprotectant for acute ischemic stroke.
- © 2012 by American Heart Association, Inc.