Which of the following neurotransmitters is the primary excitatory mediator of circular muscle contraction behind a food bolus?
Show answer and explanation
Correct answer: Acetylcholine
Acetylcholine (along with Substance P) is the major excitatory neurotransmitter released by the myenteric plexus. It binds to muscarinic receptors on smooth muscle to cause the contraction that propels the bolus forward.
Keep practicing
More Motility and peristalsis questions
- Peristalsis in the gastrointestinal tract is best described as:
- Which muscle layer contraction primarily narrows the lumen during peristalsis?
- Which nerve plexus primarily coordinates peristaltic movements?
- Which type of movement mainly serves a mixing function in the small intestine?
- The primary pacemaker cells responsible for generating slow waves are:
- Which gastrointestinal region has the slowest basic electrical rhythm?