Peristaltic reflex of the small intestine is controlled by the following:

Peristaltic reflex results from localized chemical or mechanical stimulation of the small intestine results in a contraction on the oral side of the stimulus and relaxation on the anal side. These responses are controlled by the enteric nervous system. Sensory neurons that respond to chemicals (eg, acids) or mechanical stimuli (stroking the mucosa or stretch of the muscle with a bolus of digesta) activate excitatory ascending interneurons, which then innervate excitatory motor neurons. These neurons release excitatory neurotransmitters, acetylcholine, and the neuropeptide substance P, which activates receptors on circular muscle cells to trigger contraction. The sensory neurons also excite descending interneurons that innervate inhibitory motor neurons. They, in turn, release inhibitory neurotransmitters, VIP, and nitric oxide, which relax circular muscle. Ref: Mills J.C., Stappenbeck T.S., Bunnett N. (2010). Chapter 13. Gastrointestinal Disease. In S.J. McPhee, G.D. Hammer (Eds),Pathophysiology of Disease, 6e.