Immunocytochemical staining of the RLM6 form of cytochrome P-450 in oligodendrocytes and myelin of rat brain.
We used immunocytochemical staining to localize the RLM6 form of cytochrome P-450 in rat brain. Immunofluorescence staining in vibratome sections was positive in cells that resembled oligodendrocytes, which are the cells that synthesize and maintain myelin. Double immunofluorescence staining with anti-RLM6, plus mouse monoclonal antibodies (MAb) against 2',3'-cyclic nucleotide-3'-phosphohydrolase or galactocerebrosides, showed localization of each of these oligodendrocyte "markers" in the same cells as RLM6. In vibratome sections from brains of adult rats there was faint RLM6 immunostaining in some of the myelinated fibers as well as in oligodendrocytes. In paraffin sections from adult rat brains, myelinated tracts were RLM6 positive, as were oligodendrocytes and myelinated fibers in the gray matter. Oligodendrocytes were also shown to contain glucose-6-phosphate dehydrogenase. We suggest that RLM6, which is constitutive to liver, is also constitutive to brain and, via the acetone monooxygenase reaction, which also utilizes NADPH, may contribute to the conversion of ketone bodies to substrates that could provide energy for the synthesis and maintenance of myelin.
Cammer
W
W
Dept. of Neurology, Albert Einstein College of Medicine, Bronx, NY 10461.
Downing
M
M
Clarke
W
W
Schenkman
J B
JB
D063309:2',3'-Cyclic Nucleotide 3'-Phosphodiesterase; D015087:2',3'-Cyclic-Nucleotide Phosphodiesterases / Q000032:analysis; D000818:Animals; D001933:Brain Stem / Q000166:cytology / Q000201:enzymology*; D019392:Cytochrome P-450 CYP2E1; D003577:Cytochrome P-450 Enzyme System / Q000032:analysis*; D005455:Fluorescent Antibody Technique; D005699:Galactosylceramides / Q000032:analysis; D005954:Glucosephosphate Dehydrogenase / Q000032:analysis; D007657:Ketone Bodies / Q000378:metabolism; D009186:Myelin Sheath / Q000201:enzymology*; D009836:Oligodendroglia / Q000201:enzymology*; D010089:Oxidoreductases, N-Demethylating / Q000032:analysis*; D010727:Phosphoric Diester Hydrolases; D051381:Rats; D011919:Rats, Inbred Strains
D005699:Galactosylceramides; D007657:Ketone Bodies; D003577:Cytochrome P-450 Enzyme System; D005954:Glucosephosphate Dehydrogenase; D019392:Cytochrome P-450 CYP2E1; D010089:Oxidoreductases, N-Demethylating; D015087:2',3'-Cyclic-Nucleotide Phosphodiesterases; D010727:Phosphoric Diester Hydrolases; D063309:2',3'-Cyclic Nucleotide 3'-Phosphodiesterase; C571338:Cnp protein, mouse; C571339:Cnp protein, rat