Cytochrome oxidase activity is increased in +/Lc Purkinje cells destined to die

• Published in: Neuroreport Vol. 12; no. 14; p. 3039
• Main Authors: Vogel, M W, Fan, H, Sydnor, J, Guidetti, P
• Format: Journal Article
• Language: English
• Published: England 08.10.2001
• Subjects: Aging - genetics; Animals; Animals, Newborn - metabolism; Dendrites - enzymology; Dendrites - pathology; Electron Transport Complex IV - genetics; Electron Transport Complex IV - metabolism; Energy Metabolism - genetics; Female; Histocytochemistry; Male; Membrane Potentials - genetics; Mice; Mice, Neurologic Mutants - metabolism; Nerve Degeneration - enzymology; Nerve Degeneration - genetics; Nerve Degeneration - physiopathology; Purkinje Cells - enzymology; Purkinje Cells - pathology; Receptors, Glutamate - genetics; Receptors, Glutamate - metabolism; Up-Regulation - genetics
• ISSN: 0959-4965; 1473-558X
• DOI: 10.1097/00001756-200110080-00012

+/Lc Purkinje cells degenerate postnatally because of a gain-of-function mutation in the delta2 glutamate receptor (Grid2) that causes a constitutive Na+ current leak. The effect of the resulting chronic depolarization on Purkinje cell metabolism was investigated by measuring levels of cytochrome oxidase (COX) activity in Purkinje cell dendrites using quantitative densitometry. Analysis of wild type controls and +/Lc mutants at P10, P15 and P25 showed that levels of COX activity were significantly increased above control levels by P15 and continued to increase through P25. The increase in COX activity is likely to reflect an increase in oxidative phosphorylation to accommodate the energy demands of removing excess Na+ and Ca2+ entering the Purkinje cells in response to the Grid2 leak current.