Fig. 6

Oxidative stress markers in plasma and vascular endothelial cells. a 3-nitrotyrosine (3-NT) expression in vascular endothelial cells. b P47phox expression in vascular endothelial cells. c 8-isoprostaglandin levels in plasma. d Malondialdehyde (MDA) levels in plasma. e MDA levels in vascular endothelial cells. f Glutathione peroxidase (GSH-PX) activities in vascular endothelial cells. SAL (SAL group rats underwent 48 h infusions with saline); g Dihydroethidium (DHE)-fluorescence microtopography was used to assess the effects of glucose treatment on aortic reactive oxygen species (ROS) production. Representative microscope images are shown. Red fluorescence indicates ROS formation whereas green fluorescence represents basal laminae autofluorescence. h Densitometric quantification of the DHE-derived ROS signal in the endothelium of vessels. CHG (CHG group rats underwent 48 h infusions with 50 % glucose continually to keep the glucose concentration at 20 ± 0.5 mmol/l); AFG (AFG group rats underwent 48 h infusions with 50 % glucose intermittently so that blood glucose alternated between 5.5 ± 0.5 and 20 ± 0.5 mmol/l). Data are mean ± SD. n = 10/group. *P < 0.05 vs SAL; ^#P < 0.05 vs CHG