Pancreatic Cells | Their Types and Functions
Pancreatic cells control many important physiological functions in our body.
Unlike other glands in the body, the pancreas is both an endocrine and exocrine gland.
Due to its endocrine function, it helps in the maintenance of blood glucose levels and body growth.
By its exocrine functions, it helps in digestion of food such that the nutrients are easily absorbed.
The pancreas is located below the stomach and secretes its exocrine enzymes into the small intestine.
There are broadly three types of cells in the pancreas as
- Acinar cells
- Islets of Langerhans.
- Pancreatic stellate cells
Acinar cells: These cells perform an exocrine function. They synthesize the digestive enzymes and secrete them into the intestine.
In general, they secrete enzymes like amylase, trypsin, chymotrypsin, lipase, nucleases.
Islets of Langerhans: These cells perform the endocrine function. They are of 4 types again as
- Alpha cells (α-cells)
- Beta cells (β-cells)
- Delta cells (δ-cells)
Alpha cells: These cells secrete glucagon. They constitute about 17% of the total pancreatic islets of Langerhans cells. The glucagon hormone secreted helps in the conversion of glycogen into glucose. It helps in break down of glucagon from the liver and enhances its levels in the blood.
Beta cells: These cells secrete the hormone insulin. They constitute about 70% of the total pancreatic Langerhans cells. The insulin as you might have already known decreases blood glucose levels. It enhances formation of glycogen which is stored in liver.f
Delta cells: These are the cells which secrete hormone somatostatin. They constitute about 7% of the total pancreatic islets of Langerhans cells. This hormones act as a growth hormone-inhibiting hormone and helps in the regulation of our body height.
F-cells: These cells secrete pancreatic polypeptides. These inhibit contraction of gall bladder and secretion of digestive enzymes.
Also interestingly somatostatin inhibits secretion of glucagon and insulin from the respective cells while polypeptides from F-cells inhibit secretion of somatostatin.
Pancreatic stellate cells (PSC): These cells are located in the exocrine area of the pancreas. They comprise 4-7% of the total pancreatic cells. They help in the repair of injured portions of the pancreas. They also help in the destruction of tumor cells.
They exist in either form as activated PSC or quiescent PSC. Their role is shown in the picture below.
References: Principles of Anatomy and Physiology by G.Toratorat