When the sympathetic nervous system is stimulated, the interstitial cells of Cajal, pacemaker cells of the GI tract, react by
A) decreasing amplitude or abolishing the slow waves that control the spontaneous oscillations in membrane potentials.
B) increasing the peristaltic motion of the GI tract, thereby causing explosive diarrhea.
C) increasing the amount of secretions being entered into each segment of the intestinal tract.
D) signaling the vagus nerve to slow down motility and increase absorption of water from the large intestine.

Question

Quizplus · Accepted Answer

The interstitial cells of Cajal that are found in groups between the layers of smooth muscle tissue are hypothesized to function as the pacemakers. These cells display rhythmic, spontaneous oscillations in the membrane potentials, called slow waves, ranging in frequency from approximately 3 per minute in the stomach to 12 per minute in the duodenum. The vagus nerve responds to parasympathetic innervation. GI motility is enhanced because of increased vagal activity that could cause diarrhea.

When the Sympathetic Nervous System Is Stimulated, the Interstitial Cells