HRE TBL 3 - Pancreas, Glucose and Diabetes

Which artery primarily supplies the body and tail of the pancreas?

Splenic artery

What is the main blood supply to the head of the pancreas?

Superior and inferior pancreaticoduodenal arteries

Which vein primarily drains the pancreas?

Portal vein (via splenic and superior mesenteric veins)

Where is referred pain from pancreatic inflammation typically felt?

Epigastrium radiating to the back

What spinal segments mediate referred pain in pancreatitis?

T5–T9 via greater splanchnic nerves

From which embryonic layer does the pancreas originate?

Endoderm

Which buds give rise to the pancreas?

Ventral and dorsal pancreatic buds

What does the ventral pancreatic bud form?

Uncinate process and inferior part of the pancreatic head

What does the dorsal pancreatic bud form?

Pancreatic body, tail, and superior head

When do the pancreatic buds fuse during development?

Week 6

What causes pancreas divisum?

Failure of dorsal and ventral duct fusion

What is the consequence of pancreas divisum?

Impaired drainage → recurrent pancreatitis

What causes annular pancreas?

Abnormal migration of the ventral bud

What is the clinical result of annular pancreas?

Constriction of the duodenum (duodenal obstruction)

When do islets of Langerhans begin to secrete insulin?

Weeks 10–12

What are the exocrine cells of the pancreas called?

Acinar cells

What do pancreatic acinar cells secrete?

Digestive enzymes (amylase, lipase, proteases)

What is the function of centroacinar cells?

Start of the duct system, secrete bicarbonate

Name the four cell types in the islets of Langerhans.

Alpha, beta, delta, and PP (F) cells

What hormone do alpha cells secrete?

Glucagon

What hormone do beta cells secrete?

Insulin

What hormone do delta cells secrete?

Somatostatin

What hormone do PP cells secrete?

Pancreatic polypeptide

What is the role of somatostatin?

Inhibits insulin, glucagon, and exocrine secretion

What pancreatic enzyme activates other zymogens?

Trypsin (activated from trypsinogen)

Which enzyme activates trypsinogen?

Enterokinase (enteropeptidase)

What stimulates pancreatic enzyme secretion?

CCK and parasympathetic stimulation

What inhibits pancreatic secretion?

Somatostatin

Which pancreatic structure is in direct contact with the duodenum?

Pancreatic head

What structure lies posterior to the pancreas?

Inferior vena cava

What vertebral level does the pancreas lie at?

L1–L2

Which part of the pancreas is intraperitoneal?

Tail

Which glucose transporter is insulin-dependent?

GLUT-4

Where is GLUT-4 found?

Skeletal muscle and adipose tissue

Where is GLUT-2 found?

Liver and pancreatic beta cells

What is the function of GLUT-2 in beta cells?

Glucose sensing for insulin release

What triggers insulin release from beta cells?

High intracellular ATP from glucose metabolism

What ion influx leads to insulin exocytosis?

Calcium (Ca²⁺)

What transporter brings glucose into beta cells?

GLUT-2

What channels close in response to ATP rise in beta cells?

ATP-sensitive potassium (K⁺) channels

What is the effect of insulin on glucose uptake?

Increases glucose uptake via GLUT-4 translocation

What is the main action of glucagon?

Increases blood glucose via gluconeogenesis and glycogenolysis

What receptor does glucagon bind to?

GPCR (Gs protein-coupled receptor)

What second messenger mediates glucagon action?

cAMP

Which hormone inhibits both insulin and glucagon?

Somatostatin

Which glucose transporter is used by neurons?

GLUT-3

Which transporter is used in red blood cells?

GLUT-1

Which glucose transporter is for fructose?

GLUT-5

What causes type 1 diabetes mellitus?

Autoimmune destruction of pancreatic beta cells

Which HLA types are associated with type 1 diabetes?

HLA-DR3 and HLA-DR4

What immune cells mediate type 1 diabetes?

CD4+ and CD8+ T cells

What causes type 2 diabetes mellitus?

Insulin resistance and beta-cell dysfunction

What are the key features of type 2 diabetes?

Hyperglycemia, insulin resistance, impaired secretion

What is the primary defect in type 2 diabetes?

Peripheral insulin resistance

Name three long-term complications of diabetes.

Retinopathy, nephropathy, neuropathy

What is the most serious acute complication of type 1 diabetes?

Diabetic ketoacidosis (DKA)

What causes ketone production in DKA?

Lipolysis and hepatic conversion of free fatty acids

Name two major ketone bodies.

Beta-hydroxybutyrate and acetoacetate

What is the acid-base disturbance in DKA?

High anion gap metabolic acidosis

What electrolyte abnormality is seen in DKA?

Hyperkalemia (despite total body K⁺ loss)

What causes K⁺ shift out of cells in DKA?

Lack of insulin and acidosis

What is the treatment for DKA?

IV fluids, insulin, and electrolyte correction

What is hyperosmolar hyperglycemic state (HHS)?

Severe hyperglycemia without ketosis (type 2 DM)

What is the major difference between DKA and HHS?

Absence of significant ketosis in HHS

What hormone increases during fasting?

Glucagon

What hormones counteract hypoglycemia?

Glucagon, cortisol, epinephrine, growth hormone

What does insulin stimulate in the fed state?

Glycogenesis, lipogenesis, and protein synthesis

What process provides glucose during early fasting?

Glycogenolysis

What process provides glucose during prolonged fasting?

Gluconeogenesis

What fuel is used by the brain during starvation?

Ketone bodies

What is the function of ghrelin?

Stimulates appetite (hunger hormone)

Where is ghrelin produced?

Stomach

What is the function of leptin?

Inhibits appetite and regulates energy expenditure

Where is leptin produced?

Adipose tissue

What is oxyntomodulin?

Gut hormone that promotes satiety

Which hormones influence the gut-brain axis?

Ghrelin, leptin, oxyntomodulin

What is the mechanism of action of metformin?

Reduces hepatic gluconeogenesis and increases insulin sensitivity

What is the mechanism of sulfonylureas?

Increase insulin release by blocking K⁺ channels in beta cells

How do SGLT2 inhibitors work?

Block renal glucose reabsorption → glucosuria

What is the mechanism of GLP-1 receptor agonists?

Increase insulin, decrease glucagon, slow gastric emptying

When is insulin therapy used?

In all type 1 diabetes and some advanced type 2 diabetes

What is amylin and what does it do?

Co-secreted with insulin; slows gastric emptying and suppresses glucagon

Which enzyme class is inhibited by DPP-4 inhibitors?

Dipeptidyl peptidase-4 (DPP-4), prolonging incretin action

What is the primary cause of weight gain in diabetes?

Chronic hyperinsulinemia and reduced energy expenditure

How does adipose tissue affect insulin resistance?

Releases inflammatory cytokines and free fatty acids

What is the effect of exercise on insulin sensitivity?

Increases insulin sensitivity in muscle

Which transporter allows renal glucose reabsorption?

SGLT2 in the proximal tubule

What is the role of hepatic glycogen in glucose homeostasis?

Maintains blood glucose during short-term fasting

What is the main source of glucose during prolonged fasting?

Protein catabolism for gluconeogenesis

How does cortisol affect blood glucose?

Increases gluconeogenesis and insulin resistance

What is the effect of epinephrine on glucose metabolism?

Stimulates glycogenolysis and inhibits insulin

How does growth hormone affect metabolism?

Increases lipolysis and antagonizes insulin action

Which artery supplies the uncinate process of the pancreas?

Inferior pancreaticoduodenal artery

Which developmental week does the ventral pancreatic bud rotate?

Week 6

What does the accessory pancreatic duct drain?

Proximal dorsal pancreatic duct

Which duct does the main pancreatic duct join before entering the duodenum?

Common bile duct

Through which papilla does the main pancreatic duct open into the duodenum?

Major duodenal papilla

Which papilla does the accessory pancreatic duct open into?

Minor duodenal papilla

What causes duodenal obstruction in annular pancreas?

Encirclement of the duodenum by pancreatic tissue

What anatomical structure lies anterior to the pancreas?

Stomach