21.20: Cells and Secretions of the Pancreas
The pancreas, a vital organ within the abdominal cavity, plays dual roles in the digestive and endocrine systems, collaborating with exocrine and endocrine cells to maintain optimal digestion and blood sugar levels.
Exocrine function is carried out by acinar cells, organized into clusters known as acini. These cells contribute to digestion by releasing substantial quantities of enzyme-rich, alkaline digestive juices.
Concurrently, the dispersed clusters of endocrine cells throughout the pancreas are called the islets of Langerhans. Four primary types of endocrine cells are recognized for their roles in blood glucose regulation.
Alpha cells, responsible for producing glucagon, stimulate the liver to release stored glucose, elevating blood sugar levels. On the other hand, beta cells synthesize insulin, a hormone that facilitates glucose uptake by the body's cells, thereby reducing blood sugar levels.
Delta cells produce somatostatin, also known as the growth hormone-inhibiting hormone, which plays a regulatory role by inhibiting insulin and glucagon release. Another endocrine cell type, the pancreatic polypeptide (PP) cells, produces the pancreatic polypeptide, influencing the rate of nutrient uptake in the intestines.
This intricate interplay between exocrine and endocrine components ensures the pancreas' multifaceted contribution to digestion and blood sugar regulation, highlighting its essential role in maintaining overall metabolic balance.
