“…The key feature describing the ENS during its development is the neuronal plasticity in the expression of neurotransmitters, in particular VIP, PACAP (Pituitary Adenylate Cyclase-activating Polypeptide), galanin and nitric oxide (NO) (for references see: Ekblad and Sundler, 2002). The development of GI motility and its neurohormonal regulation was a matter of extensive studies in the past century (for references see: Ekblad and Sundler, 2002;Ceregrzyn and Kuwahara, 2002). However, most of the studies were performed in guinea pig small intestinal tissue and mostly in vitro.…”