Part 6: Acetylcholine on digestive Smooth Muscle Questions: 11) Did smooth muscle behave the same as cardiac muscle when treated with Acetylcholine? 12) Is this what you expect from parasympathetic stimulation of digestive smooth muscle? 13) How is it possible that they have different reactions? Explain in terms of receptor types. 14) Which changed more, the contraction time or the relaxation time for this smooth muscle?.