Elevation of Na+-K+ ATPase immunoreactivity in GABAergic neurons in gerbil CA1 region following transient forebrain ischemia.
In a previous study, we suggested that GABAergic neurons might be resistant to ischemic insult, because of the maintenance of the GABA shunt, which is one of the ATP synthetic pathways in neurons. In the present study, we identified Na(+)-K(+) ATPase immunoreactivity in the gerbil hippocampus in order to determine whether changes in Na(+)-K(+) ATPase immunoreactivity correlate with GABA shunt following ischemic insult. At 12 h after ischemia-reperfusion, Na(+)-K(+) ATPase immunoreactivity accumulated in some neurons in the CA1 region. However, the protein content of Na(+)-K(+) ATPase was not altered. Interestingly, the density of Na(+)-K(+) ATPase immunoreactivity in neurons and the protein content in the CA1 region was intensified in the 24 h post-ischemic group. As a result of double immunofluorescence study, Na(+)-K(+) ATPase immunoreactive neurons were identified with GABAergic neurons. Therefore, our findings suggest that the increase of Na(+)-K(+) ATPase in GABAergic neurons may be able to explain the resistance of these cells to ischemic insult, and support our previous hypothesis that GABA may play an important role as a metabolite in the survival of GABAergic neurons after ischemic insult.
Kang
Tae-Cheon
TC
Department of Anatomy, College of Medicine, Hallym University, Kangwon-Do, Chunchon 200-702, South Korea.
Hwang
In Koo
IK
Park
Seung-Kook
SK
An
Sung-Jin
SJ
Nam
Young Sam
YS
Kim
Do-Hoon
DH
Lee
In Se
IS
Won
Moo Ho
MH
D000818:Animals; D015153:Blotting, Western; D005849:Gerbillinae; D005968:Glutamate Decarboxylase / Q000378:metabolism; D006624:Hippocampus / Q000033:anatomy & histology / Q000201:enzymology*; D007150:Immunohistochemistry; D002546:Ischemic Attack, Transient / Q000201:enzymology* / Q000378:metabolism; D008297:Male; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013997:Time Factors
D005968:Glutamate Decarboxylase; D000254:Sodium-Potassium-Exchanging ATPase