Exam 2 - Diabetes Pathophysiology Flashcards
diabetes
metabolic disorder characterized by hyperglycemia that results from defects in insulin secretion and/or insulin action
what does regulating glucose depend on
- the liver
- it extracts glucose
- synthesizes it into glycogen (energy storage)
- glycogenolysis (breakdown glycogen)
pancreas
- in connection with the liver it controls the body’s fuel supply of glucose/insulin
endocrine function
cells secrete insulin directly into the blood stream
pancreatic islet
- small islands of cells within the pancreas that make up the endocrine function
- alpha cells
- beta cells
alpha cells
secrete glucagon in response to low blood sugar
glucagon
stimulates the liver to release stored glucose in the blood
beta cells
produce insulin
- which lowers glucose levels by stimulating the movement of glucose into body tissues
hormones that raise blood glucose levels
- glucagon
- epinephrine
- glucocorticoids
- growth hormone
insulin
- hormone secreted by the pancreas (beta cells)
- stimulates uptake, utilization, and storage of glucose
- stimulates the liver to store glucose
- decreases plasma concentrations of glucose
insulin and lipid metabolism
- insulin promotes synthesis of fatty acids in the liver
- insulin inhibits the breakdown of fat in adipose tissue
- insulin drives cells to use carbohydrates instead of fat for energy
what happens when you don’t have enough insulin
- cannot breakdown carbohydrates efficiently
- decreased glucose use by cells
- hyperglycemia
- cells have to use alternate sources of energy = fatty acids
- impaired fat metabolism
- increased lipolysis (fat breakdown)
- decreased lipogenesis (formation of fat)
free fatty acids (FFA)
- alternate energy source for tissues
- excess is converted to cholesterol and phospholipids
- breaks down to acetyl-CoA
ketone bodies
substance that are composed of these acid breakdown products
short term complications of impaired fat metabolism
- increased serum ketones
- ketosis
- measured by blood and urine levels of ketones
- ketosis can cause severe metabolic acidosis (coma)
long term complications of impaired fat metabolism
atherosclerosis because of high serum lipid levels