Diabetes Patho (Exam 2) Flashcards
Diabetes
-An epidemic in the united states.
-Over 30 million people. 10% of the populations
What is Diabetes?
-A metabolic disorder characterized by HYPERGLYCEMIA that results from defects in insulin secretion, insulin action or both
-It is associated with extensive long term damage when uncontrolled to multiple organ systems
Carbohydrates
-Simple sugars and complex chemical units
-Are broken down in the duodenum and proximal jejunum
Carbohydrates in a healthy person
-Temporarily spikes glucose then lowers back down to baseline
Diabetes: Liver
-Regulating glucose depends on the LIVER.
-Extracts glucose (from the blood)
-Synthesizes it into glycogen (energy storage)
-Glycogenolysis (breakdwon glycogen)
How does the liver help our peripheral tissues?
The liver helps out peripheral tissues by extracting glucose from the blood, synthesizes the glucose into glycogen, then breaking down the glycogen for energy (glycogenolysis)
Diabetes: The pancreas
-In connection with the liver it controls the body’s fuel supply (glucose/insulin)
2 major functions of the pancrease
-Exocrine
-Endocrine
Exocrine functions of the Pancreas
-Pancreatic cells secrete directly into ducts (not blood stream) (Digestive enzymes directly into the duct)
Endocrine function of the Pancreas
-Cells secrete Insulin directly into blood stream
-What we are focusing on
Pancreas: Islet of Langerhans
-Islets are small islands of cell within the pancreases that make up the endocrine function
-Islets of langerhans has both alpha and beta cells
Alpha Cells
-Island of Langerhans
-Secrete glucagon in response to low blood sugar
-Glucagon thus stimulates the liver to release stored glucose into the blood
Beta cells
-Islet of Langerhans
-Produce insulin, which lowers glucose levels by stimulating the movement of glucose into body tissues
Insulin does what to blood glucose
LOWER
Hormones that raise blood glucose levels
-Glucagon (Islet)
-Epinephrine (Andrenal Medulla)
-Glucocorticoids (Adrenal cortex)
-Growth hormone (anterior pituitary)
Balancing Act of Hormones
Insulin
-Beta Cells in the pancreas
-Stimulates uptake, utilization, and storage of glucose
-Stimulates the liver to store glucose (as glycogen)
-Because of the stimulating effects above- insulin decreases plasma concentrations of glucose
Insulin and Lipid Metabolism
-Insulin promotes synthesis of fatty acids in the liver. (This occurs once the liver has been saturated with glycogen)
-Insulin inhibits the breakdown of fat in adipose tissue (Can cause a buildup of triglycerides in fat cells)
-On the whole, Insulin has a fat-sparing effect, and drives cells to use carbohydrates instead of fat or energy
What happens when you dont have enough insulin
-Cannot breakdown carbohydrate efficiently
-Decreased glucose use by cells
-Rapid build up of glucose in blood = HYPERGLYCEMIA
-Cells have to use alternate sources of energy = fatty acids
What happens when you gont have enough insulin pt.2
-Impaired fat metabolism also occurs. (increased lipolysis) (Decrease lipogenesis)
Impaired Fat Metabolism from not having enough insulin causes
-Free fatty acids in your blood
-FFA are an alternate energy source for tissues
-Excess FFA is converted to cholesterol and phospholipids
-FFA breaks down to acetyl-CoA (Used by liver or to acetoacetic acid)
Ketone Bodies
Occurs when FFA from impaired fat metabolism breaks down into acetyl-CoA…Ketone bodies are created
Complication of Impaired Fat Metabolism: Short term
-These increase in serum ketones can cause Ketosis
-Ketosis can cause severe metabolic acidosis—-COMA
-Ketones measured by blood and urine levels