Brain creatine kinase and creatine transporter proteins in normal and creatine-treated rabbit pups.
Systemic creatine (Cr) supplementation increases brain phosphocreatine (PCr) and prevents hypoxic seizures in 15-day-old rabbits. Between 5 and 30 days of age during normal development, rabbit gray matter mitochondrial creatine kinase (Mi-CK) increases 400% while cytosolic CK (BB-CK) increases 60%. In white matter, both isoenzymes show smaller, similar increases (40%) during this period. The Cr transporter protein decreases 60% between 5 and 15 days in both regions. In vivo CK rate constants measured by (31)P nuclear magnetic resonance increase 30% between 10 and 20 days, and then fall 50% between 20 and 30 days in predominantly gray matter slices. Similar maturational changes are seen in predominantly white matter slices. Injecting Cr at 15 days does not significantly change BB-CK or Mi-CK isoenzymes or the in vivo CK reaction rate constants. Thus, the largest change in the CK system associated with suppression of hypoxic seizures in Cr-treated rabbits is increased PCr in gray and white matter.
Kekelidze
T
T
Department of Radiology, Brigham and Women's Hospital and Harvard Medical School, Boston, MA 02115, USA. tkeke@bwh.harvrd.edu
Khait
I
I
Togliatti
A
A
Holtzman
D
D
D000375:Aging / Q000378:metabolism; D000818:Animals; D001921:Brain / Q000378:metabolism*; D002352:Carrier Proteins / Q000032:analysis / Q000378:metabolism*; D003401:Creatine / Q000008:administration & dosage*; D003402:Creatine Kinase / Q000032:analysis / Q000378:metabolism*; D002534:Hypoxia, Brain / Q000378:metabolism; D007527:Isoenzymes / Q000032:analysis / Q000378:metabolism; D009682:Magnetic Resonance Spectroscopy; D026901:Membrane Transport Proteins; D008928:Mitochondria / Q000201:enzymology; D010725:Phosphocreatine / Q000032:analysis / Q000096:biosynthesis; D010759:Phosphorus Isotopes / Q000032:analysis; D011817:Rabbits
D002352:Carrier Proteins; D007527:Isoenzymes; D026901:Membrane Transport Proteins; D010759:Phosphorus Isotopes; C080679:creatine transporter; D010725:Phosphocreatine; D003402:Creatine Kinase; D003401:Creatine