Background: The present study was designed to investigate in a focal cerebral ischemia model the influence of 2APH, a competitive NMDA receptor antagonist, on the cerebral blood flow of cat cortex, given intravenously before cerebral ischemia.
Methods: Thirty-four male cats weighing 2.5 to 3.5 kg were anesthetized with halothane and then randomly assigned to either control or experimental group. In the experimented group 18 cats were treated with 2APH and in the control group 16 cats were given saline 10 min before middle cerebral artery occlusion (MCAO). Cortical blood flow (CBF), determined by laser Doppler ultrasound flowmetry, was measured 1 h, 2 h, 3 h, 4 h and 5 h after occlusion. Infarct volume was calculated by summing up the areas in each stained brain section after the experiment.
Results: There was a significant difference in the infarct volume of cortex between the 2APH group and the saline control group (P < 0.05). Moreover, we did notice an apparent decrease of the infarct volume in basal ganglia area when 2APH was given (P < 0.01). The total infarct volume was significantly smaller in the group treated with 2APH after MCAO as compared with the saline control group (P < 0.01).
Conclusions: The data from the present experiment suggest that NMDA antagonists may not only antagonize the neurotoxic effect of excitatory amino acid on ischemic neuron but also improve the CBF of ischemic brain.