Intracellular Calcium Dysregulation: Implications for Alzheimer’s Disease

Figure 3

NCXs labeling patterns in neuronal mitochondria ((a)–(i)). (a and d) NCX1-ir mitochondria (arrows) in distal dendrites (CA1 stratum radiatum). ((b) and (e)) NCX2-ir mitochondria (arrows) in hippocampal (b) and neocortical (e) dendrites. (c) NCX3-ir mitochondria in neocortical distal dendrite (arrow). (f) NCX2-positive mitochondrion in a CA1 axon terminal. ((g) and (h)) NCX2 and NCX3-ir mitochondria (arrows) in a cell body (from CA1 pyramidal cell layer); enlarged in the inset in (h), two labeled organelles (arrows) near nuclear envelope. (i) NCX3-ir in neocortical distal dendrite with unlabeled mitochondria (open arrow). In (b) and (d) dendrites are contacted by axon terminals forming asymmetric junction (triangles). In (a) and (e), note the labeling bridging plasma membrane and mitochondrial profile. Open arrows indicate unlabeled mitochondria in dendrites ((a) and (i)) and axon terminals ((b) and (d)). With asterisks the postsynaptic specializations are indicated and the arrowheads show the labeling between mitochondria and plasma membrane. axt, axon terminal; den, dendrite; nu, nucleus; cyt, cytoplasm; sp, dendritic spine. Immunoperoxidase reaction in (a)–(c), (f), (g), and (h) and silver-enhanced immunogold in (d), (e), and (i). Calibration bars: in (a), 0.25 m for (a), (b), (d), (f), and (i); in (a), 0.5 m for inset in (h); in (c), 0.25 m for (c) and (e); in (c), 0.5 m for (g); in (c), 1 m for (h). The figure has been entirely reproduced from Gobbi et al., 2007 [27], upon written authorization by the editor.

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