Effects of clomethiazole on radial-arm maze performance following global forebrain ischemia in gerbils.

The functional and neuroanatomical protective effects of clomethiazole (CMZ) were examined in an animal model of global forebrain ischemia. Gerbils underwent sham-surgery or were rendered ischemic by the application of aneurysm clips to both carotid arteries for 6 min. Three treatment groups received CMZ (50 mg/kg, 100 mg/kg, or 150 mg/kg) 30 min before ischemia, and one group was given 150 mg/kg of CMZ 30 min after ischemia. Following recovery, the gerbils were tested in a radial-arm maze to assess memory functions. Histological evaluation was assessed blindly using a percentile scoring system. The results indicate that pre-ischemic treatment with 100 mg/kg and 150 mg/kg of CMZ reduced brain damage and working memory errors significantly. Treatment dosage of 150 mg/kg of CMZ was the most effective in preventing neuronal damage in the hippocampus and eliminating the working memory deficit typically induced by ischemia.