摘要
BACKGROUND： Patients with type-2 diabetes mellitus exhibit higher levels of plasma endothelin-1 （ET-1）. However, very few reports exist regarding altered endothelin-3 （ET-3） and ET-1 concentrations in brain tissue. OBJECTIVE： To observe expression changes of ET-3 and glial fibrillary acidic protein （GFAP） in the frontal and parietal cortex of type-2 diabetic mice following ischemia-reperfusion injury, with various reperfusion durations. DESIGN, TIME AND SETTING： Randomized controlled animal study. The experiment was conducted in the Xiangya Medical College of Central South University and the Third Xiangya Hospital between February 2002 and January 2003. MATERIALS： Sixty-six, adult, male, Kunming mice, weighing （30 ± 5） g, as well as rabbit anti-ET-3 polyclonal and rabbit anti-GFAP polyclonal antibodies, were provided by the Neurobiology Institute of Second Military Medical University in Japan. METHODS： Sixty-six mice were randomly divided into five groups： diabetes mellitus （DM, n = 6）, diabetes mellitus with ischemia-reperfusion （DM/IR, n = 24）, ischemia-reperfusion （IR, n = 24）, sham operation （SO, n = 6）, and control （n = 6）. MAIN OUTCOME MEASURES： Following ischemia-reperfusion for 1, 3, 5, and 10 days, respectively, expression of ET- 3 and GFAP was immunohistochemically measured in the frontal and parietal cortex. RESULTS： All 66 mice were included in the final result analysis. In the IR and DM/IR groups, ET-3- and GFAP-positive neurons increased in the frontal and parietal cortex in response to one day reperfusion, peaked at five days, and decreased at 10 days. ET-3 and GFAP expression was significantly greater in the DM/IR group after reperfusion for 1 day compared to the IR group. However, at other time points, there were no significant differences between the two groups. CONCLUSION： Brain ischemia-reperfusion injury results in overexpression of ET-3 and activation of astrocytes. Diabetes increases the number of ET-3- and GFAP-positive astrocytes in brain tissue of ischemia-reperfusion mice with the same reperfusion duration.
BACKGROUND： Patients with type-2 diabetes mellitus exhibit higher levels of plasma endothelin-1 （ET-1）. However, very few reports exist regarding altered endothelin-3 （ET-3） and ET-1 concentrations in brain tissue. OBJECTIVE： To observe expression changes of ET-3 and glial fibrillary acidic protein （GFAP） in the frontal and parietal cortex of type-2 diabetic mice following ischemia-reperfusion injury, with various reperfusion durations. DESIGN, TIME AND SETTING： Randomized controlled animal study. The experiment was conducted in the Xiangya Medical College of Central South University and the Third Xiangya Hospital between February 2002 and January 2003. MATERIALS： Sixty-six, adult, male, Kunming mice, weighing （30 ± 5） g, as well as rabbit anti-ET-3 polyclonal and rabbit anti-GFAP polyclonal antibodies, were provided by the Neurobiology Institute of Second Military Medical University in Japan. METHODS： Sixty-six mice were randomly divided into five groups： diabetes mellitus （DM, n = 6）, diabetes mellitus with ischemia-reperfusion （DM/IR, n = 24）, ischemia-reperfusion （IR, n = 24）, sham operation （SO, n = 6）, and control （n = 6）. MAIN OUTCOME MEASURES： Following ischemia-reperfusion for 1, 3, 5, and 10 days, respectively, expression of ET- 3 and GFAP was immunohistochemically measured in the frontal and parietal cortex. RESULTS： All 66 mice were included in the final result analysis. In the IR and DM/IR groups, ET-3- and GFAP-positive neurons increased in the frontal and parietal cortex in response to one day reperfusion, peaked at five days, and decreased at 10 days. ET-3 and GFAP expression was significantly greater in the DM/IR group after reperfusion for 1 day compared to the IR group. However, at other time points, there were no significant differences between the two groups. CONCLUSION： Brain ischemia-reperfusion injury results in overexpression of ET-3 and activation of astrocytes. Diabetes increases the number of ET-3- and GFAP-positive astrocytes in brain tissue of ischemia-reperfusion mice with the same reperfusion duration.
