Figure 2.

Confocal images of biocytin-filled cells.

(A) Projection of confocal image scans showing a low magnification view of the SCN to reveal the biocytin-filled (green) cell lying within the region of GFP+ (red) cells (15 μm stack of 10 scans each 1.5 μm). The fibers of this cell initially project dorsally, then orient medially toward the region of AVP+ (blue) cells, scale bar =50 μm. The right insets are confocal scans of the same cell showing biocytin (green), GFP (red), AVP (blue) staining lacking here and the overlay, confirming the peptidergic identity of the cell (Z axis = 2 μm; scale bar =10 μm). (B) Montage of a monopolar GFP+ neuron bearing appendages arising directly from the soma. The axon (white arrows) and the spiny dendrite project dorsally to the AVP+ region (blue staining; z axis = 1 μm. The montage is made up of z axis 1 μm scans taken over a total depth of 24μm. Scale bar=10 μm). Cell location is shown in a drawing of the SCN on the right. Scale bar, 50 μm. (C) Montage of a bipolar GFP+ neuron. Its axon arises proximally from the ventral dendrite, projects laterally, then dorsally, is dye coupled to another cell (small arrow) and makes appositions onto GFP+ somata (large white arrows), turns toward the medial SCN region and bifurcates (arrowhead). One branch reaches the AVP+ region and ends making contact with AVP+ cells (large right arrow). The other branch extends ventrally among GFP+ cells. One dendrite extends ventrally among GFP+ cells, while the second extends dorsomedially among AVP+ cells. The montage is made up of z axis = 1 μm scans taken over total depth of 31μm, scale bar, 10 μm. Cell location is shown in a drawing of the SCN on the right. biotin=green, GFP=red and AVP=blue. Scale bar for drawing, 50 μm. The insets above show appositions of the axon (green) of the cell in C onto an AVP+ cell (blue) and onto a GFP+ cell (red), scale bar, 10 μm.