Vasopressin has three main effects: 1  Increasing the water permeability of distal convoluted tubule and collecting duct cells in the kidney, thus allowing water reabsorption and excretion of more concentrated urine, i.e., antidiuresis.
It can be caused by damage to the vagus nerve, which regulates the digestive system. A damaged vagus nerve prevents the muscles in the stomach and intestine from functioning, preventing food from moving through the digestive system properly. Often, the cause of gastroparesis is unknown.
1 Achalasia. 2  When your lower esophageal muscle (sphincter) doesn't relax properly to let food enter your stomach, it may cause you to bring food back up into your throat. 3  Muscles in the wall of your esophagus may be weak as well, a condition that tends to worsen over time. 4  Diffuse spasm.