Figure 6. Stimulation with 200 nM adrenomedullin (ADM) increases cyclic adenosine monophosphate (cAMP)-like immunoreactivity (LI) and cyclic guanosine monophosphate (cGMP)-LI. A: In the control retinas, cAMP-LI was in isolated somata in the outer nuclear layer (ONL; horizontal arrow), in faint staining in the outer plexiform layer (OPL; asterisk), in sparse somata in the inner nuclear layer (INL; diagonal arrow), in diffuse puncta in the inner plexiform layer (IPL), and in somata in the ganglion cell layer (GCL; down arrow). B: In retinas stimulated with ADM, there was an overall increase in cAMP-LI, with increased numbers of photoreceptor somata (horizontal arrow), puncta in the OPL (asterisk), and somata in the INL (diagonal arrow) and the GCL (down arrow). C: In the control retinas, faint cGMP-LI was in some photoreceptor outer segments (vertical arrow) and in somata in the inner (diagonal arrow) and outer (horizontal arrow) ONL. D: In retinas stimulated with ADM, there was an increase in the number and intensity of labeled photoreceptor outer segments (up arrow) and somata in the inner region of the ONL (diagonal arrow). There were also some faint somata in the INL (horizontal arrow). Scale bars=20 µm.