R/M hypoglycemia increases microglial activation in the hippocampus and in the cortex. (A) Brain sections were harvested at one day after the last episode of moderate hypoglycemia and immunostained with CD11b. R/M hypoglycemia-induced microglial activation in the hippocampus and in the cerebral cortex is apparent in both non-diabetic (Saline) and diabetic (STZ) rats. Diabetic rats show substantially increased microglial activation in the hippocampal CA1, hilus, and cortex compared to non-diabetic rats. Scale bar = 100 μm. (B) Quantification of microglial activation was performed from hippocampal CA1 pyramidal area. Microglial activation is quantified based on morphological change and intensity of CD11b immunostaining. As shown in the images, microglial activation is aggravated in diabetic rats. Data are mean + s.e.m.; n = 5, * P < 0.05.