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.
Gastroparesis slows or stops the movement of food from the stomach to the small intestine. Most people diagnosed with gastroparesis have idiopathic gastroparesis, which means a health care provider cannot identify the cause, even with medical tests. Diabetes is the most common known cause of gastroparesis.