Aging: effects on sodium- and potassium-activated adenosine triphosphatase activity and ouabain binding sites in rat brain.
Sodium- and potassium-activated adenosine triphosphatase (Na,K-ATPase) activity and [3H]-ouabain binding were examined in homogenates of cerebral cortex, striatum, and hypothalamus of 3-, 8-, and 26-month-old rats to determine if aging-related alterations in energy utilization demonstrated in brain slices and homogenates are potentially associated with alterations in Na,K-ATPase. There were no consistent age-related changes seen in Na,K-ATPase activity, the number of [3H]-ouabain binding sites, or their affinity for ouabain. Moreover, enzyme activities of the two molecular forms of Na,K-ATPase and their inhibition by strophanthidin did not appear to be different in partially purified enzyme preparations obtained from whole brain of 3- and 26-month-old rats. In contrast, the concentration of [3H]-ouabain binding sites was lower in cardiac muscle of senescent rats indicating a reduction in the number of active Na,K-ATPase units. It appears unlikely that aging-related central nervous system changes are associated with alterations in the Na,K-ATPase enzyme system.
Kennedy
R H
RH
Akera
T
T
Katano
Y
Y
D000375:Aging; D000818:Animals; D001921:Brain / Q000201:enzymology* / Q000378:metabolism; D002540:Cerebral Cortex / Q000201:enzymology / Q000378:metabolism; D003342:Corpus Striatum / Q000201:enzymology / Q000378:metabolism; D007031:Hypothalamus / Q000201:enzymology / Q000378:metabolism; D008297:Male; D009206:Myocardium / Q000201:enzymology / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000032:analysis; D010042:Ouabain / Q000378:metabolism*; D051381:Rats; D011916:Rats, Inbred F344; D011955:Receptors, Drug / Q000187:drug effects / Q000378:metabolism; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism*; D013327:Strophanthidin / Q000494:pharmacology
D009419:Nerve Tissue Proteins; D011955:Receptors, Drug; C028996:cardiac glycoside receptors; D010042:Ouabain; D013327:Strophanthidin; D000254:Sodium-Potassium-Exchanging ATPase