For example, a perforation of the appendix may so unbalance the nerve apparatus as to feel it at the umbilicus. It is a reality. The secretion of the gastrointestinal mucosa is entirely beyond the control of the will. In secretions we are especially dealing with the sympathetic nerve, for secretions have a close relation to the size of the blood vessels. All glands receive vessels.
All vessels have nerves to control their caliber.
The gastric secretion may be reviewed in regard to experimental data. The stomach is supplied with nerves for its muscles and for its glands, as motion and secretion are both necessary for normal digestion. The Arrangement of the Auerbach and Billroth-Meissner plexuses is similar to the small intestines. The splanchnic nerve is the chief vasomotor nerve, i. e., vasodilator and vasoconstrictor. It is doubtless true that there are not only vasomotor nerves in the spinal cord but that the abdominal brain is a great vasomotor center, in that the abdominal brain regulates the amount of blood to the gastric glands and consequently the amount, and to a certain degree the kind, of secretion of the stomach.