Mrs. Ashley Medical Assistant Science

PANCREAS ANATOMY stomach esophagus ductus choledocus duodenum duct of Santorini duct of Wirsung pancreas

 Exocrine and endocrine cells  90% of pancreas related to exocrine (digestive function)  10% endocrine (homeostasis for glucose levels in the body)

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◦ Both an exocrine and endocrine organ ◦ Cells with exocrine function release an alkaline fluid containing sodium bicarbonate and enzymes →  pancreatic duct → small intestine ◦ Pancreatic “juice” aids in breakdown and digestion of food in the small intestine ◦ Pancreatic exocrine cells = acinar cells

 Acinar cells - exocrine cells of the pancreas that produce and transport digestive enzymes  Amylase, lipase, phospholipase, proteases (trypsinogen, chymotrypsinogen)

PANCREATIC SECRETIONS 1. PROTEASES (70%) Endopeptidases (trypsin, chymotrypsin, elastases) Exopeptidases (carboxypeptidases) trypsinogen trypsin activates all other precursors enterokinase (duct walls) 2. NUCLEASES (DNAase, RNAase) 3. PANCREATIC AMYLASE (hydrolyse starch and gl;ycogen) 4. PANCREATIC LIPASE (triglycerides fatty acids and glycerol)

PANCREAS (PANORAMIC) pancreatic acini islet of Langerhans islet of Langerhans BV pancreatic lobe

 Islets of Langerhans - endocrine cells of the pancreas that produce and secrete hormones into the bloodstream  Glucagon - Alpha cells (A cells) - raises the level of glucose (sugar) in the blood by causing liver to break down stored glycogen  Insulin - Beta cells (B cells) - stimulates cells to use glucose and reduce glucose levels in blood  Antagonistic Hormones

11 Endocrine Function : Cells of the Islet of Langerhans synthesize and release hormones into the circulation. Hormones travel through the bloodstream to target tissues (especially liver and muscle) At the target cells, hormones bind specific receptors and cause cell changes that control metabolism

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13  Chemically – high levels of glucose and amino acids in the blood  Hormonally – beta cells are sensitive to several hormones that may inhibit or cause insulin secretion  Neurally – stimulation of the parasympathetic nervous system causes insulin to be secreted.

14  Transported through the blood to target tissues where it binds to specific receptors  The binding of insulin to target cells: ◦ Acts as a biochemical signal to the inside of the cell  Overall, cell metabolism is stimulated  There is increased glucose uptake into the cell  Regulation of glucose breakdown within the cell  Regulation of protein and lipid breakdown within the cell

 Blood glucose is decreased because insulin causes glucose to leave the bloodstream and enter the metabolizing cells.  With the exception of brain, liver and erythrocytes, tissues require membrane glucose carriers.

 Inflammation of the pancreas

 Pancreas suddenly becomes inflamed  Causes: Gallstones Ethanol Trauma Steroids Mumps Autoimmune Scorpion venom Hyperlipidaemia, hypothermia ↑Ca 2+ Drugs

Symptoms  epigastric and central abdominal pain  vomiting and nausea  swollen and tender abdomen  fever  dehydration and low blood pressure Diagnosis  medical history and physical exam  blood test: ↑ amylase, lipase  abdominal ultrasound, Endoscopic Ultrasound, CT scan

Treatment  nothing to eat or drink  intravenous fluids  analgesia  ERCP and gallstone removal Complications  shock, Acute respiratory distress syndrome, renal failure, Disseminated intravascular coagulation, sepsis, ↓Ca 2+  pancreatic necrosis, pseudocyst, abscesses, bleeding, thrombosis

 inflammation of the pancreas - gets worse over time and leads to permanent damage Causes: many years of alcohol use hereditary disorders of the pancreas cystic fibrosis haemochromatosis autoimmune conditions

Symptoms  nausea and vomiting  weight loss  diarrhea  steatorrhea

Treatment  drugs - analgesia, lipase, fat-soluble vitamins  diet  surgery – pancreatectomy pancreaticojejunostomy Complications  pseudocyst, diabetes, biliary obstruction, local arterial aneurysm, splenic vein thrombosis

 The single most common endocrine disorder – group of glucose intolerance disorders  Incidence is estimated at 8.3% of the North American population  35% are pre-diabetic  Many of these cases are undiagnosed

25 Historically ‑ distinguished by weight loss, excessive urination, thirst, hunger Excessive urination = polyuria Excessive thirst = polydipsia Excessive hunger = polyphagia Modern characterization is by hyperglycemia and other metabolic disorders

 increased level of glucose in the blood (normal blood glucose level mmol/l) 90 mg/100ml Type 1 ( insulin-dependent DM, IDDM)  destruction of insulin-secreting pancreatic β cells (autoimmune response)  juvenile diabetes-tends to begin in early childhood  patient always needs insulin

Type 2 (non-insulin dependent DM, NIDDM)  insulin resistance  Β cell dysfunction, ↓insulin secretion Causes of insulin resistance:  metabolic syndrome (central obesity, hyperglycaemia, hypertension, ↓HDL cholesterol, ↑triglycerides)  renal failure  pregnancy  cystic fibrosis  polycystic ovarian syndrome

28 Glucose in urine- Because when insulin is not present, glucose is not taken up out of the blood at the target cells. So blood glucose is very highly increased → increased glucose filtered and excreted in the urine (exceeds transport maximum)

Mechanisms of insulin resistance:  post-receptor defects in insulin action  gene mutation  circulating autoantibodies

Diagnosis  blood glucose level  urine sample  HbA1c test

Treatment:  diet  oral hypoglycaemics

33 Control diet Carbohydrates should make up about 55-60% of patient’s total calories Fats should make up <30% of patient’s total calories Proteins should make up about 15-20% of patient’s total calories

34 Monitor exercise Remember: muscles are a target tissue of insulin, and metabolize much glucose for energy Sometimes exercise → irregular blood glucose levels So diabetic patients should be monitored when they are exercising

 insulin injections (long-acting, short- acting, rapid-acting)  insulin pen  insulin pump therapy

Complications

 diabetec ketoacidosis  hypoglycaemia  diabetic retinopathy

 atherosclerosis (heart disease and stroke)  neuropathy (diabetic foot care)

 Age over 40 years  Diabetes during a previous pregnancy  Excess body weight  Family history of diabetes  Dyslipidaemia (large amount of lipids in body)  Hypertension  Low activity level  Metabolic syndrome  Polycystic ovarian syndrome  Acanthosis nigricans- darkening and thickening of skin