title: Dynamic turnover of mouse brain phospholipids during normal aging and response to ischemia.
abstract: An in vivo labeling procedure was used to probe the dynamic turnover of mouse brain phospholipids and to evaluate the response of these phospholipids toward decapitation ischemic insult. Within 4 hr after intracerebral injection of [32P]-ATP, the label was effectively incorporated into all phospholipids and uniquely in all subcellular membrane fractions examined. With respect to age, synaptosomes isolated from the 27-month-old mice group showed a higher incorporation of label into polyphosphoinositides and phosphatidic acids and a lower incorporation into the neutral phospholipids than the 10-month-old group. The increase in labeling of these phospholipids with age seems to reflect the increase in basal level of substrates for phosphorylation of phosphoinositol 4-phosphate and diacylglycerols. The increase in substrate level is probably related to a decrease in metabolic turnover of the lipids underlying the phosphoinositide cycle. Decapitation ischemic insult is known to result in a rapid time-dependent breakdown of the polyphosphoinositides in brain. However, a comparison of the ischemia-induced breakdown of polyphosphoinositide between the 10 and 27 month-old groups did not reveal obvious age differences in the rate of their disappearance.
authors.affiliation: Sinclair Comparative Medicine Research Farm, University of Missouri, Columbia.
authors.forename: G Y
authors.initials: GY
authors.lastname: Sun
authors.forename: T N
authors.initials: TN
authors.lastname: Lin
mesh_terms: D000375:Aging / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000378:metabolism*; D002545:Brain Ischemia / Q000378:metabolism*; D002855:Chromatography, Thin Layer; D008297:Male; D051379:Mice; D008810:Mice, Inbred C57BL; D010743:Phospholipids / Q000378:metabolism*
chemical_list: D010743:Phospholipids