Why does enteric nervous system (ENS) activation during digestion cause increased intestinal motility in the small intestine rather than decreased motility?

💡 Explanation

The ENS increases intestinal motility because substance P, released by ENS neurons, directly stimulates contraction of intestinal smooth muscle, which promotes peristalsis and movement of chyme through the small intestine; therefore, motility increases, rather than decreases, because of excitatory neurotransmitters, rather than inhibitory influences, dominating the ENS response.

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