'Hot spots' of creatine kinase localization in brain: cerebellum, hippocampus and choroid plexus.
Creatine kinase (CK) isoenzymes, with emphasis on the mitochondrial CK isoenzymes, were characterized and localized in chicken cerebellum. Chicken cerebellum extracts analyzed by two-dimensional gels, using antipeptide antibodies specific for sarcomeric muscle-type mitochondrial CK (Mib-CK) and revealed the presence of a Mib-CK variant in avian cerebellum. This CK isoform was localized by immunofluorescence staining exclusively in the Purkinje neurons. The co-expression of this Mib-CK together with cytosolic muscle-type MM-CK, as observed in the same Purkinje neurons, may reflect the specific energy requirements associated with highly fluctuating Ca2+ levels (Ca2+ spiking) in these specialized neurons. Ubiquitous brain-type mitochondrial Mia-CK was found together with cytosolic BB-CK mainly in the glomeruli structures of the cerebellar granular layer. BB-CK, but much less so Mia-CK however, was also very prominent in Bergmann glial cells of the two mitochondrial Mi-CK isoenzymes in the chicken cerebellum is demonstrated. Other hot spots of CK localization were the granule and pyramidal cells of the hippocampus in rat. There, a developmental stage-dependent immunofluorescence staining, especially with antibodies against Mia-CK was noted. Epithelial cells of the choroid plexus were also highly enriched in CK. The possible implications of a CK/PCr circuit at these various cellular locations of the brain are discussed with respect to normal brain physiology and pathology.
Kaldis
P
P
Swiss Federal Institute of Technology, ETH-Hönggerberg, Zürich, Switzerland.
Hemmer
W
W
Zanolla
E
E
Holtzman
D
D
Wallimann
T
T
D000818:Animals; D002531:Cerebellum / Q000201:enzymology*; D002645:Chickens; D002831:Choroid Plexus / Q000201:enzymology*; D003402:Creatine Kinase / Q000378:metabolism*; D015180:Electrophoresis, Gel, Two-Dimensional; D005455:Fluorescent Antibody Technique; D006624:Hippocampus / Q000201:enzymology*; D007527:Isoenzymes / Q000378:metabolism*; D008856:Microscopy, Fluorescence; D008928:Mitochondria / Q000201:enzymology; D051381:Rats; D014018:Tissue Distribution
D007527:Isoenzymes; D003402:Creatine Kinase