Elevation of the gamma-aminobutyric acid transaminase expression in the gerbil CA1 area after ischemia-reperfusion damage

gamma -Aminobutyric acid-transaminase (GABA-T) plays an important role in t he metabolism of GABA, particularly in the neurons or glial cells. The pres ent study was undertaken to determine the alteration of GABA-T expression i n the gerbil hippocampus after ischemia-reperfusion. In the sham, GABA-T+ n eurons were scattered in the hippocampus proper and dentate gyrus. The inte nsity of the GABA-T immunoreactivity had nearly disappeared in the interneu rons at 12 h after ischemia. In contrast, 24 h post-ischemia the dramatic a ugmentation of GABA-T immunoreactivity in the pyramidal cells was observed in the CA1 area but not in the CA2 or CA3 areas. Forty-eight hours after is chemia-reperfusion, its immunoreactivity was preserved in the CA1 neurons. These results suggest that the over-expression of GABA-T in the CA1 area ma y be related to delayed neuronal death after ischemia-reperfussoo insult. ( C) 2000 Published by Elsevier Science Ireland Ltd.