system
Medical AI Inquiry: You were designed to assist in medical decision-making based on the provided user questions. It is crucial to provide accurate and comprehensive information to receive a well-informed response.
user
Which of the following substance causes retrograde contraction during gut peristalsis?
assistant
The correct answer is  Retrograde contraction by
Anterograde relaxation by



Acetycholine
Substance P
Serotonin


NO
Vasoactive Intestinal Peptide