Change of peroxisome proliferator-activated receptor γ expression pattern in the gerbil dentate gyrus after transient global cerebral ischemia

Peroxisome proliferator-activated receptor γ (PPARγ) has various actions including the regulation of adipocyte differentiation, lipid metabolism and glucose homeostasis. In the present study, we examined the changes of PPARγ immunoreactivity and protein levels in the gerbil dentate gyrus (DG) after transient global cerebral ischemia using immunohistochemistry and western blot analysis. PPARγ immunoreactivity was gradually increased from 1 day after ischemia-reperfusion. PPARγ immunoreactivity, in accordance with protein level, was highest at 2 days after ischemia-reperfusion and was detected in microglia at this time. Thereafter, both PPARγ immunoreactivity and protein level were decreased with time in the ischemic DG. These results indicate that PPARγ may be related to the ischemia-induced microglial activation and neuronal damage/death in the DG after transient global cerebral ischemia.