Clomethiazole protects the brain in transient forebrain ischemia when used up to 4 h after the insult.

Brief periods of forebrain ischemia result in consistent damage in the hippocampus in gerbils. This damage can be attenuated by free radical scavengers, glutamate antagonists and GABA agonists. Most of the work with cerebral protection has been done with agents infused prior to the insult. In this experiment we tested clomethiazole, a GABA agonist, as a neuroprotective agent 1 and 4 h after a 5 min ischemic insult (bilateral carotid occlusion) in gerbils. Damage was assessed using silver staining techniques at 7 days after the insult. There were 10 animals in each group. Clomethiazole was given subcutaneously at a dose of 100 mg/kg. Compared to controls, there was significant protection in the CA1 (P < 0.01) and CA4 (P < 0.01) regions of the hippocampus at 1 and 4 h after the ischemic insult. GABAergic agents may play an important role in neuronal protection when used after ischemic insults.