Nerve fibers in porcine GI tract immunostained for CART (A, D, G, J, M) and VIP (B, E, H, K) or CGRP (N); merged in C, F, I, L, O. A–F: jejunal muscularis externa. G–I: duodenal villi. J–L: duodenal glands of Brunner. M–O: muscularis mucosae of the antrum. Note high degree of colocalisation of CART and VIP in all GI segments, except for the muscularis mucosae, where CART is colocalised with CGRP. Colocalisation exemplified with arrowheads. Scale bars = 50 μm.