Expression and changes of Ca2+-ATPase in neurons and astrocytes in the gerbil hippocampus after transient forebrain ischemia.
Ca2+-ATPase is one of the most powerful modulators of intracellular calcium levels. In this study, we focused on chronological changes in the immunoreactivity and protein levels of Ca2+-ATPase in the hippocampus after 5 min of transient forebrain ischemia. Ca2+-ATPase immunoreactivity was significantly altered in the hippocampal CA1 region and in the dentate gyrus, but not in the CA2/3 region after ischemic insult. In the sham-operated group, Ca2+-ATPase immunoreactivity was detected in the hippocampus. Ca2+-ATPase immunoreactivity in the CA1 region and in the dentate gyrus, and its protein levels peaked 3 h after ischemic insult. At this time, CA1 pyramidal cells and dentate polymorphic cells showed strong Ca2+-ATPase immunoreactivity. Thereafter, Ca2+-ATPase immunoreactivity reduced in the CA1 region and in the dentate gyrus. One day after ischemic insult, Ca2+-ATPase immunoreactivity was observed in some CA1 non-pyramidal cells, and 4 days after ischemic insult, Ca2+-ATPase immunoreactivity was detected in astrocytes throughout the CA1 region, but Ca2+-ATPase immunoreactivity in the dentate gyrus had nearly disappeared. Our results suggest that Ca2+-ATPase changes may be associated with a response to ischemic damage in hippocampal CA1 pyramidal cells, and that increased Ca2+-ATPase immunoreactivity in the reactive astrocytes may be associated with the maintenance of intracellular calcium levels.
Shin
Hyoseon
H
Department of Anatomy, College of Medicine, Hallym University, Chunchon 200-702, South Korea.
Hwang
In Koo
IK
Yoo
Ki-Yeon
KY
Song
Ji-Hyun
JH
Jung
Ju-Young
JY
Kang
Tae-Cheon
TC
Choi
Soo Young
SY
Han
Byoung Hee
BH
Kim
Jong Sung
JS
Won
Moo Ho
MH
D000818:Animals; D001253:Astrocytes / Q000201:enzymology*; D000252:Calcium-Transporting ATPases / Q000378:metabolism*; D016923:Cell Death; D005849:Gerbillinae; D006624:Hippocampus / Q000166:cytology / Q000201:enzymology*; D007150:Immunohistochemistry; D002546:Ischemic Attack, Transient / Q000201:enzymology*; D008297:Male; D009474:Neurons / Q000201:enzymology; D016548:Prosencephalon / Q000098:blood supply* / Q000201:enzymology; D017966:Pyramidal Cells / Q000166:cytology / Q000201:enzymology*; D013997:Time Factors; D014018:Tissue Distribution
D000252:Calcium-Transporting ATPases