Fig. 2.

Spinally projecting neurons as targets for axons projecting from the NTS. Views of the dorsal cap region of PVN showing NTS axons (black) with close appositions to the cell bodies (A, A′) and dendrites (B, B′) of the cholera toxin-labelled spinally projecting presympathetic neurons (brown). (A′) Multiple axons (arrowhead) wound around cells where synaptic boutons (arrow) apposed the cell soma. Similarly, axons (B′) can be observed to traverse cell bodies in their passage through the PVN. These axons had numerous boutons (arrow) interspersed by non-bouton regions (arrowhead). (C) A deconvolved image showing the course of an axon (green) as it crossed the cell soma of a FG-labelled presympathetic neuron (blue) with multi bouton appositions over the cell soma (arrow). (C′) An isosurface 3-D rendered view of (C) revealing the close association between the green NTS boutons (arrows) with the preautonomic neurons (blue). Scale bars A, B = 60 μm; A′ = 6 μm; B′ = 30 μm; C = 15 μm; C′ = 8 μm. (For interpretation of the references to colour in this figure legend, the reader is referred to the web version of this article.)