Previous studies have indicated that electrical stimulation of the cerebellar fastigial nucleus in rats may reduce brain infarct size, increase the expression of Ku70 in cerebral ischemia/reperfusion area, and decrease the number of apoptotic neurons. However, the anti-apoptotic mechanism of Ku70 remains unclear. In this study, fastigial nucleus stimulation was given to rats 24, 48, and 72 hours before cerebral ischemia/reperfusion injury. Results from the electrical stim-ulation group revealed that rats exhibited a reduction in brain infarct size, a signiifcant increase in the expression of Ku70 in cerebral ischemia/reperfusion regions, and a decreased number of terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL)-positive cells. Double immunofluorescence staining revealed no co-localization of Ku70 with TUNEL-positive cells. However, Ku70 partly co-localized with Bax protein in the cytoplasm of rats with cerebral ischemia/reperfusion injury. These ifndings suggest an involvement of Ku70 with Bax in the cy-toplasm of rats exposed to electrical stimulation of the cerebellar fastigial nucleus, and may thus provide an understanding into the anti-apoptotic activity of Ku70 in cerebral ischemia/reperfu-sion injury.

Brain-derived neurotrophic factor is associated with the insulin signaling pathway and glucose tabolism. We hypothesized that expression of brain-derived neurotrophic factor and its receptor may be involved in glucose intolerance fol owing ischemic stress. To verify this hypothesis, this study aimed to observe the changes in brain-derived neurotrophic factor and tyrosine kinase B receptor expression in glucose metabolism-associated regions fol owing cerebral ischemic stress in mice. At day 1 after middle cerebral artery occlusion, the expression levels of brain-derived neurotrophic factor were significantly decreased in the ischemic cortex, hypothalamus, liver, skeletal muscle, and pancreas. The expression levels of tyrosine kinase B receptor were decreased in the hypothalamus and liver, and increased in the skeletal muscle and pancreas, but remained unchanged in the cortex. Intrahypothalamic administration of brain-derived neurotrophic factor (40 ng) suppressed the de-crease in insulin receptor and tyrosine-phosphorylated insulin receptor expression in the liver and skeletal muscle, and inhibited the overexpression of gluconeogenesis-associated phosphoenolpy-ruvate carboxykinase and glucose-6-phosphatase in the liver of cerebral ischemic mice. However, serum insulin levels remained unchanged. Our experimental findings indicate that brain-derived neurotrophic factor can promote glucose metabolism, reduce gluconeogenesis, and decrease blood glucose levels after cerebral ischemic stress. The low expression of brain-derived neurotrophic factor fol owing cerebral ischemia may be involved in the development of glucose intolerance.