The pancreas is a gland situated behind the stomach. This organ plays a role in converting ingested food into energy for the body’s cells. It carries out two distinct functions, each managed by specialized types of tissue.
Exocrine Tissue and Digestion
The majority of the pancreas consists of exocrine tissue. This tissue is organized into functional units composed of acinar cells and ductal cells. Acinar cells synthesize and secrete digestive enzymes. These enzymes are released into pancreatic ducts.
Ductal cells lining these ducts transport the digestive enzymes and secrete bicarbonate and water. The bicarbonate helps neutralize acidic contents from the stomach in the duodenum. This neutralization creates an optimal environment for the enzymes to function.
Enzymes include amylase, which breaks down carbohydrates, and lipase, which breaks down fats. Proteases such as trypsin and chymotrypsin digest proteins. These enzymes activate in the duodenum, facilitating food breakdown for nutrient absorption.
Endocrine Tissue and Hormone Control
Small clusters of cells, known as the Islets of Langerhans, make up the endocrine portion of the pancreas. These islets account for about 1% to 2% of the pancreas’s total volume. These clusters produce and release hormones directly into the bloodstream to regulate metabolic processes.
Main cell types are beta and alpha cells. Beta cells, about 70% of islet cells, produce insulin. Insulin lowers blood glucose by signaling cells to absorb glucose for energy or storage.
Alpha cells, about 20% of islet cells, produce glucagon. Glucagon raises blood glucose by prompting the liver to release stored glucose. This opposing action maintains balanced blood sugar, important for organs like the brain and kidneys.
When Pancreas Tissue Is Damaged
Damage to pancreatic tissue can disrupt its functions, leading to various health conditions. Pancreatitis, an inflammation of the pancreas, occurs when digestive enzymes from the exocrine tissue become prematurely activated. This premature activation leads to the enzymes attacking and damaging the pancreatic tissue. Common causes of pancreatitis include gallstones and chronic alcohol use.
Pancreatic cancer often originates from exocrine ductal cells. This cancer involves uncontrolled multiplication of cells lining the ducts. Symptoms often appear late in the disease’s progression, making early detection challenging. Type 1 diabetes results from an autoimmune process where the immune system attacks and destroys insulin-producing beta cells. This leads to insufficient insulin production, causing high blood sugar.
Examining and Analyzing Pancreas Tissue
Healthcare providers employ various methods to examine pancreatic tissue. Imaging tests are often the first step to visualize the organ’s structure and identify abnormalities.
Computed Tomography (CT) scans use X-rays to create detailed images of the pancreas, helping to detect tumors or inflammation. Magnetic Resonance Imaging (MRI) uses radio waves and magnets to produce detailed images of soft tissues, revealing pancreatic diseases like pancreatitis, cysts, or lesions. Magnetic Resonance Cholangiopancreatography (MRCP) visualizes bile and pancreatic ducts, detecting blockages or tumors.
To confirm a diagnosis, a biopsy may be performed. During this procedure, a thin needle is guided into the pancreas, often with endoscopic ultrasound (EUS), to collect a tissue sample for analysis.