Anatomy lec 3

• Pancreas

  In Greek: Pan=all, kreas=fleshy
• Pancreas

  • Exocrine gland of the digestive system
  • Hormone producing endocrine gland
• Exocrine function of pancreas


  Synthesis and release of digestive enzymes into the duodenum
• Endocrine function of pancreas

  Release of insulin and glucagon into the bloodstream to regulate glucose, lipid, and protein metabolism
• Pancreas

  • Elongated organ (J shaped)
  • Length: approximately 15 cm
• Anatomical parts of pancreas


  • Head
  • Uncinate process
  • Neck
  • Body
  • Tail
• Head of pancreas


  • Expanded medial part, lies directly against the descending and horizontal parts of the C-shaped duodenum
• Uncinate process


  • Projecting inferiorly from the head, extends posterior to the superior mesenteric artery
• Neck of pancreas


  • Short structure of approximately 2 cm continuing laterally from the head, connecting the head with the body. Posterior to the neck are the superior mesenteric artery and vein and the origin of the portal vein.
• Body of pancreas


  • Consists of three surfaces (anterior, inferior and posterior) and three borders (superior, anterior and inferior). Located anterior to the L2 vertebra. Forms the floor of the omental bursa (lesser sac).
• Tail of pancreas


  • The last part of the pancreas, closely related to the hilum of the spleen and runs with the splenic vessels in the splenorenal (lienorenal) ligament.
• Main pancreatic (Wirsung) duct


  Travels within the entire pancreatic parenchyma from the tail to the head, connects with the bile duct in the head of the pancreas to form the hepatopancreatic duct (the ampulla of Vater) which opens into the descending part of the duodenum at the major duodenal papilla.
• Accessory pancreatic duct


  Communicates with the main pancreatic duct at the level of the pancreatic neck, opens into the descending part of the duodenum at the minor duodenal papilla above the major duodenal papilla.
• Arterial supply to pancreas


  • Pancreatic branches of the splenic artery
  • Superior and inferior pancreaticoduodenal arteries (branches of the gastroduodenal and superior mesenteric arteries respectively)
• Venous drainage of pancreas

  • Anterior superior pancreaticoduodenal vein (empties into superior mesenteric vein)
  • Posterior superior pancreaticoduodenal vein (empties into portal vein)
  • Anterior and posterior inferior pancreaticoduodenal veins (drain into superior mesenteric vein)
  • Pancreatic veins draining body and tail (empty into splenic vein)
• Nerve supply to pancreas


  • Parasympathetic innervation from vagus nerve (CN X)
  • Sympathetic innervation from greater and lesser splanchnic nerves (T5-T12)
• Lymphatic drainage of pancreas


  • Body and tail (drain to pancreaticosplenic lymph nodes along splenic artery)
  • Head (drain to pyloric lymph nodes, then to superior mesenteric or celiac lymph nodes)
• Suprarenal (adrenal) glands


  • Paired, retroperitoneal
  • Related to upper pole of kidney
  • Yellowish color
  • RT: pyramidal, LT: semi-lunar
  • Size: at birth 1/3 size of kidney, in adult 1/30th size of kidney
• Relations of adrenal glands


  • Anterior: Inferior vena cava, right lobe of liver, right crus of diaphragm, stomach, pancreas, spleen, left crus of diaphragm
  • Posterior: Perinephric (renal) fascia, perirenal fat
• Adrenal gland structure


  • Outer connective tissue capsule, cortex, medulla
  • Cortex derived from embryonic mesoderm, medulla derived from neural crest cells
• Adrenal cortex regions


  • Zona glomerulosa (produces mineralocorticoids)
  • Zona fasciculata (produces corticosteroids, small amount of androgens)
  • Zona reticularis (produces androgens, small amount of corticosteroids)
• Adrenal medulla


  Contains chromaffin cells that secrete catecholamines (adrenaline) and enkephalins
• Adrenal arteries


  • Superior adrenal artery (from inferior phrenic artery)
  • Middle adrenal artery (from abdominal aorta)
  • Inferior adrenal artery (from renal arteries)
• Adrenal veins


  • Right adrenal vein (drains into inferior vena cava)
  • Left adrenal vein (drains into left renal vein)
• Adrenal innervation


  • Sympathetic innervation via coeliac plexus and greater splanchnic nerves (T10-L1)
  • Parasympathetic innervation
• Adrenal lymphatic drainage


  • To lumbar lymph nodes via adrenal lymphatic vessels originating from capsular and medullary plexuses