Electron microscopic immunolabeling of transporters and receptors identifies transmitter-specific functional sites envisioned in Cajal's neuron.

摘要: Neuronal arborizations that were so elegantly demonstrated in the early drawings of Santiago Ramon y Cajal can now be viewed by high resolution electron microscopic immunocytochemical localization vesicular and plasmalemmal neurotransmitter transporters receptors. The subcellular distribution these proteins confers both chemical selectivity functional specificity to dendritic axonal described Cajal. This is illustrated central dopaminergic cholinergic neurons. Dopamine terminals striatum ventral pallidum, as well dendrites midbrain neurons tegmental area substantia nigra express dopamine transporter (DAT) monoamine (VMAT2). In forebrain regions, D2 receptor (D2R) autoreceptor localized terminals, but also targeted pre- postsynaptic neuronal profiles at a distance from terminals. somata neurons, D2R labeling expressed most contain VMAT2 storage vesicles, excitatory inhibitory afferents. Together, observations indicate stored released vesicles dendrities axons, may activate either local or more distant receptors through volume transmission. By analogy, acetylcholine (VachT) similarly membranes axon tubulovesicles mesopontine nuclei, suggesting there release axons. These results identify chemically selective sites for signaling envisioned redefined modern technology.