Figure 9.

MOR-immunoreactivity in the RVM appears to be unchanged after SNL. A, MOR immunoreactivity in RVM ipsilateral to sham surgery. B, MOR immunoreactivity in RVM ipsilateral to SNL. RVM neurons, including TPH-IR neurons expressed MOR immunoreactivity after SNL. Section was double-stained; insets show expression of MOR immunoreactivity by TPH-IR RVM neurons. Insets were taken from the region outlined by the square. C, Absorption control. Section of RVM serially adjacent to that in B; note marked reduction in labeling. Section was also double-stained and the same TPH-IR neurons visible in B can be seen in the insets. Again, the square indicates the region from which the insets were taken. Scale bar in insets, 30 μm. The 300 μm scale bar in C applies to A–C.