Function of SERCA mediated calcium uptake and expression of SERCA3 in cerebral cortex from young and old rats.
Previous work on peripheral sympathetic neurons indicated that a decline in sarco/endoplasmic reticulum calcium ATPase (SERCA) function occurs with advancing age. Therefore, an age-related decline in mechanisms controlling intracellular calcium homeostasis could contribute to altered neuronal function and/or degeneration. In this study we sought to extend the findings on peripheral neurons and to detect possible age-related declines in SERCA function and expression of SERCA3 in central neurons from cerebral cortex from young (6-month) and old (20-month) rats. Functional studies compared ATP-dependent 45Ca(2+)-uptake into microsomes and plasma membrane vesicles (PMVs). We and found no significant difference in 45Ca(2+)-uptake between microsomes or PMVs between young and old animals. On the other hand expression of SERCA3 mRNA in rat cerebral cortex showed a significant decline with advancing age. However, comparison of SERCA3 protein content did not reveal a corresponding decline; implying that SERCA mRNA turnover rates may be greater in the younger group. Although the present work with rat cerebral cortex does not indicate an age-related decline in SERCA function, previous work from our laboratory on sympathetic nerves and by others on the hippocampus indicate such a decline. In light of our previous and current studies, aging may affect calcium homeostatic mechanisms in central and peripheral autonomic neurons differently.
Pottorf
W J
WJ
Department of Pharmacology, Loma Linda University School of Medicine, Loma Linda, CA 92350, USA.
De Leon
D D
DD
Hessinger
D A
DA
Buchholz
J N
JN
D000375:Aging / Q000502:physiology*; D000818:Animals; D002118:Calcium / Q000378:metabolism* / Q000493:pharmacokinetics; D000252:Calcium-Transporting ATPases / Q000235:genetics / Q000378:metabolism*; D002462:Cell Membrane / Q000187:drug effects / Q000201:enzymology; D002540:Cerebral Cortex / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D004791:Enzyme Inhibitors / Q000494:pharmacology; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology; D006706:Homeostasis / Q000235:genetics; D007424:Intracellular Fluid / Q000187:drug effects / Q000201:enzymology; D008297:Male; D008861:Microsomes / Q000187:drug effects / Q000201:enzymology; D009410:Nerve Degeneration / Q000201:enzymology* / Q000503:physiopathology; D009474:Neurons / Q000166:cytology / Q000187:drug effects / Q000201:enzymology*; D020033:Protein Isoforms / Q000235:genetics / Q000378:metabolism; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism; D051381:Rats; D011916:Rats, Inbred F344; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases; D013347:Subcellular Fractions / Q000187:drug effects / Q000201:enzymology; D019284:Thapsigargin / Q000494:pharmacology; D022161:Transport Vesicles / Q000187:drug effects / Q000201:enzymology*
C506951:Atp2a3 protein, rat; D004791:Enzyme Inhibitors; D020033:Protein Isoforms; D012333:RNA, Messenger; D019284:Thapsigargin; D053498:Sarcoplasmic Reticulum Calcium-Transporting ATPases; D000252:Calcium-Transporting ATPases; D002118:Calcium