*2*.*1*. *Experimental Animals*

Animal care and surgical procedures were performed in accordance with guidelines approved by the National Institutes of Health (Bethesda, MD, USA) and the Josai University Animal Research Committee. Male Sprague-Dawley rats (4 weeks old, weight 120–140 g) were purchased from Japan SLC (Shizuoka, Japan) and were housed under standard conditions with a temperature-controlled environment (23 °C ± 0.5 °C) and a 12 h light/dark cycle. The animals were allowed free access to rodent chow (CE-2, CLEA Japan, Tokyo, Japan) and water. Type 1 diabetes was induced in the rats (diabetic group) by a single intraperitoneal injection of STZ (50 mg/kg of body weight) dissolved in 0.1 mM sodium citrate, pH 4.5, while the normal control rats (nondiabetic group) were injected with the buffer only [26]. Seven days after the injection of STZ, a blood sample was collected by tail vein paracentesis, following which plasma glucose was measured using a glucose analyzer (Ascensia,

Bayer Yakuhin, Osaka, Japan). Diabetes was defined as a blood glucose level greater than 300 mg/dL. Then, the diabetic and nondiabetic groups were divided into 2 groups and were housed for an additional 6 weeks until stroke was induced by MCAO/Re. AA (L-Ascorbic acid, Wako Pure Chemicals Industries, Osaka, Japan) (100 mg/kg; nondiabetic and diabetic AA-supplemented groups) or distilled water (nondiabetic and diabetic control groups) was orally administered through nasogastric tube once daily for the last 2 weeks. AA was stored at +4 °C, and dissolved in distilled water fresh each time just before administration.
