Fig. 3. PRXamide-like immunoreactivity (PRXa-LI) in fifth-instar R. prolixus. Ventral views of (A) brain, (B) sub-oesophageal ganglion, (C) prothoracic ganglion (PRO) and (D) the mesothoracic ganglionic mass. In A, note the lateral immunoreactive cells (open arrows). In B, note the numerous bilaterally paired cell bodies (open arrows) lying medially. In C, note the lightly staining immunoreactive varicosities over the ventral PRO. In D, note the immunoreactive cell bodies (open arrows) and extensive neurohaemal-like immunoreactivity on the abdominal nerves (closed arrows). The intensity of staining of these cells is greatly reduced 3–4 h following feeding (see later). Scale bar, 100 µm.