What is the endocrine part present in the tail of the pancreas?

Endocrine Components in the Tail of the Pancreas

The tail of the pancreas contains primarily beta cells and alpha cells as its main endocrine components, with beta cells comprising the majority (89-96%) of the endocrine tissue in this region. 1

Distribution of Endocrine Cells in the Pancreatic Tail

• The endocrine pancreas consists of the islets of Langerhans, which make up approximately 2% of the total pancreatic mass but play a critical role in glucose homeostasis 2
• Beta cells (insulin-producing) are the predominant endocrine cell type in the tail of the pancreas, where 89-96% of VMAT2 staining (a marker used to identify endocrine tissue) co-localizes with insulin 1
• Alpha cells (glucagon-producing) are also present in the tail region but in smaller numbers compared to beta cells 3
• PP cells (pancreatic polypeptide-producing) are heterogeneously distributed throughout the pancreas, comprising only about 0.41-0.58% of the body and tail regions, compared to 1.58% in the pancreatic head 1
• Delta cells (somatostatin-producing) are present in smaller numbers throughout the pancreas, including the tail region 4

Functional Significance of Endocrine Cells in the Pancreatic Tail

• The primary function of beta cells is the tight regulation of blood glucose levels through insulin secretion 3
• Alpha cells produce glucagon, which works antagonistically to insulin to raise blood glucose levels when they fall too low 2
• The relative distribution of these cells in the tail region is important for proper glucose homeostasis and metabolic function 5
• The tail region of the pancreas is often targeted for imaging studies when assessing beta cell mass, as it contains a higher proportion of beta cells relative to PP cells compared to the head of the pancreas 1

Clinical Relevance

• In diabetes assessment, the body and tail of the pancreas are often used as reference points for measuring beta cell mass using radiotracers like [18F]FP-DTBZ, as these regions have less interference from PP cells 1
• For surgical interventions involving pancreatic neuroendocrine tumors in the tail, distal pancreatectomy (with or without splenectomy) is the standard approach 1
• Pancreatic endocrine tumors can arise from any of the cell types in the islets, with insulinomas (from beta cells) being the most common functioning tumors (up to 70%) 1
• The tail of the pancreas can be accessed for islet transplantation or as a site for "reporter islets" that can be monitored to assess pancreatic endocrine function 6

Research Applications

• The endocrine cells in the tail of the pancreas can serve as "reporter islets" when transplanted to optically accessible locations (such as the eye's anterior chamber), allowing for real-time monitoring of islet function and response to treatments 6
• Nuclear hormone receptor expression studies in the endocrine pancreas have identified potential therapeutic targets for diabetes treatment by examining the differential expression patterns in alpha and beta cells 2