How much dopamine is in the human brain?
Dopamine
In the pancreas the role of dopamine is somewhat complex. The pancreas consists of two parts, an exocrine and an endocrine component.  The exocrine part synthesizes and secretes digestive enzymes and other substances, including dopamine, into the small intestine.[66] The function of this secreted dopamine after it enters the small intestine is not clearly established—the possibilities include protecting the intestinal mucosa from damage and reducing gastrointestinal motility (the rate at which content moves through the digestive system).[66]