The pancreas, a unique organ in the digestive and endocrine systems, is crucial for maintaining blood sugar levels and aiding digestion. Located in the abdomen behind the stomach, this mixed gland known as a heterocrine gland has both endocrine and exocrine functions. Approximately 99% of the pancreas is dedicated to exocrine activity, while the remaining 1% serves endocrine roles, supporting a balance of hormones and enzymes essential for various bodily functions.
As an endocrine gland, the pancreas regulates blood glucose by releasing insulin, glucagon, somatostatin, and pancreatic polypeptide. Specialized cells within the pancreatic islets manage these secretions: beta cells release insulin to lower blood glucose when levels are high, while alpha cells release glucagon to increase glucose when levels are low. Somatostatin, released by delta cells, inhibits both insulin and glucagon, supporting glucose balance (homeostasis) in the blood. Insulin’s function extends beyond glucose regulation; it facilitates protein and fat synthesis and is pivotal for cellular glucose uptake, especially in muscle and fat tissues.
The pancreas also plays an essential role in digestion as an exocrine gland. It produces pancreatic juice, a blend of bicarbonate and digestive enzymes that help break down carbohydrates, proteins, and fats. This juice is delivered to the duodenum, the first part of the small intestine, where bicarbonate neutralizes acidic content from the stomach, creating a suitable environment for enzyme activity.
Structurally, the pancreas is divided into sections: the head, neck, body, and tail. The head, located within the curvature of the duodenum, is connected to major blood vessels, such as the superior mesenteric artery and vein. The neck lies between the head and body, anterior to the portal vein, while the body is the largest part, situated behind the stomach and alongside major vessels like the aorta. This unique positioning allows the pancreas to interact with nearby organs and tissues.
Diseases of the pancreas include pancreatitis, an inflammation often caused by alcohol use or gallstones, and pancreatic cancer, a condition with a poor prognosis due to late detection. The pancreas’s endocrine role also connects it to diabetes, a condition that arises from issues with insulin production or function.
