Cryo sections of colon from rats treated with saline (b, c, e, g, j) or buserelin (a, d, f, h) immunostained with human neuronal protein HuC/D (green) and calcitonin gene-related peptide (CGRP), cocaine- and amphetamine-related transcript (CART), galanin, gastrin-releasing peptide (GRP), neuropeptide Y (NPY), nitric oxide synthase (NOS), somatostatin (som), substance P (SP), and vasoactive intestinal peptide (VIP)(red). Micrographs are merged and show intense immunostaining, irrespective of treatment. Arrowheads indicate HuC/D-immunoreactive myenteric neurons also immunoreactive to CGRP (a), CART (b), and NOS (f). Arrows indicate a HuC/D-immunoreactive submucous neuron also immunoreactive to galanin (c), GRP (d), NPY (e), som (g), and VIP (j). In micrograph (h), SP-immunoreactive fibers innervate a myenteric ganglia. Scale bar = 20 μm applies for all the micrographs in Figure 3.