title: The effect of moderate hypocapnic ventilation on nuclear Ca2+-ATPase activity, nuclear Ca2+ flux, and Ca2+/calmodulin kinase IV activity in the cerebral cortex of newborn piglets.
abstract: Previous studies have shown that hypocapnia results in fragmentation of nuclear DNA in the cerebral cortex of newborn piglets. We tested the hypothesis that hypocapnia results in decreased ATP and phosphocreatine (PCr) levels and increased nuclear high-affinity Ca++-ATPase activity, intranuclear Ca++ flux, and CaM kinase IV activity in neuronal nuclei of piglets. Three groups of piglets were ventilated as either hypocapnic (a PaCO2 of 20 mm Hg), normocapnic (a PaCO2 of 40 mm Hg), or corrected hypocapnic (ventilated as hypocapnic but with CO2 added to maintain normocapnia) for 1 h. Tissue ATP levels were lower in the hypocapnic than in the normocapnic group. PCr levels were lower and 45Ca++-influx, Ca++-ATPase activity and CaM kinase IV activity were higher in hypocapnic than in normocapnic or corrected hypocapnic piglets. We conclude that hypocapnia alters nuclear membrane Ca++ flux mechanisms and may alter neuronal phosphorylation mechanisms in the cerebral cortex of piglets.
authors.affiliation: Department of Pediatrics, Drexel University College of Medicine, St. Christopher's Hospital for Children, Neonatology Research Laboratories, Philadelphia, Pennsylvania 19134, USA. Karen.I.Fritz@Drexel.edu
authors.forename: Karen I
authors.initials: KI
authors.lastname: Fritz
authors.forename: Alan B
authors.initials: AB
authors.lastname: Zubrow
authors.forename: Qazi M
authors.initials: QM
authors.lastname: Ashraf
authors.forename: Om P
authors.initials: OP
authors.lastname: Mishra
authors.forename: Maria
authors.initials: M
authors.lastname: Delivoria-Papadopoulos
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D002118:Calcium / Q000378:metabolism*; D054734:Calcium-Calmodulin-Dependent Protein Kinase Type 4; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000378:metabolism*; D000252:Calcium-Transporting ATPases / Q000378:metabolism*; D002467:Cell Nucleus / Q000201:enzymology* / Q000378:metabolism; D002540:Cerebral Cortex / Q000201:enzymology / Q000378:metabolism*; D017136:Ion Transport; D010725:Phosphocreatine / Q000378:metabolism; D013552:Swine
chemical_list: D010725:Phosphocreatine; D054734:Calcium-Calmodulin-Dependent Protein Kinase Type 4; D017871:Calcium-Calmodulin-Dependent Protein Kinases; D000252:Calcium-Transporting ATPases; D002118:Calcium