Gastric Motility Network model architecture.

The GMN is constituted of a chain of nearest-neighbor coupled interstitial cells of Cajal (ICC) and associated smooth muscle (SM) cells. The ICCs have electrical and second messenger (Ca²⁺ and IP₃) based coupling, while the ICC to SM and SM to SM couplings are only electrical. There is a negative gradient in enteric neural innervation (β) that modulates IP₃ production rate along the rostrocaudal ICC chain (ICC index). Key variables and their interconnections impacting the functionality of an ICC are illustrated in the enlarged inset. The bold arrows in the inset show the inflows and outflows of key variables. The dashed arrows indicate dependency of the sink variable on the source variable. The dashed arrows with (+) sign highlight the positive feedback pathways important for intrinsic pacemaking by an ICC. See Table 1 and text for further details.