Physiology of Pancreas

The pancreas has both endocrine and exocrine functions. In 1869, Langerhans described the islet cells of the pancreas. In 1921, Banting and Best isolated pancreatic extract containing insulin from the islet cells. Sanger and his associates in 1955 elucidated the chemical structure of insulin.

The endocrine portion of the pancreas consists of clusters of cells called islets of Langerhans. Four kinds of cells are found in these clusters-

1. α (A) Cells (20%) – Glucagon
2. β (B) Cells (70%) ‑ Insulin
3. δ (D) Cells (<5%) ‑ Somatostatin
4. F Cells (<5%) ‑ Pancreatic polypeptide (PP)

Insulin and glucagon are often secreted and act reciprocal­ly, Glucagon and insulin are concerned with regulation of blood sugar level.