Diabetes Patho Flashcards
Diabetes mellitus
Metabolic dx char by inc blood sugar from relative or absolute insulin deficiency; assoc with long-term damage to multiple systems when uncontrolled
Where carbs are broken down primarily
Duodenum and proximal jejunum
Blood glucose level pattern in normal people
Increase when carbs taken in, then decrease
Liver’s role in blood sugar
Liver extracts glucose from blood, synthesizes it into glycogen and can break down glycogen in glycogenolysis if needed; peripheral fat and muscle extracts glucose if needed
Pancreas role
Produces insulin and controls blood sugar with the liver
Exocrine function of pancreas (UNIMPORTANT)
Secrete directly into ducts (not blood)
Endocrine function of pancreas and location
Cells secrete insulin directly into blood; occurs in islet of langerhans (cell island in pancreas with several types of cells)
Alpha cells
Part of islet of langerhans; secrete glucagon in response to low blood sugar
Glucagon
Stimulates liver to release stored glucose (glycogen) into blood
Beta cells
Located in islet of langerhans; make insulin which decreases glucose levels by stimulating the movement of glucose into body tissue
Insulin
Stimulates uptake, use and storage of glucose by acting like a key to open cells in the liver so they can store glucose as glycogen; ultimately decreases blood plasma concentrations of glucose (Dec blood sugar)
Hormones that increase blood glucose levels
Glucagon, epinephrine, glucocorticoids, growth hormone
What role does insulin play in lipid metabolism?
- promotes synthesis of fatty acids in the liver after the liver has been saturated with glycogen
- inhibits b/d of fat in adipose tissue—build up of TGs in fat cells;
- in healthy, ins has fat-sparing effect and drives cells to use carbs instead of fat for energy
What happens if you lack insulin?
Can’t b/d carbs well, decrease glucose use by the cells, rapid increase of blood glucose—hyperglycemia, cells use fatty acids instead
Insulin deficiency causes…
Dec glucose uptake by the cells (Hyperglycemia), Proteolysis (protein b/d), lipolysis (fat b/d)
Impaired fat metabolism
Occurs from insulin deficiency; causes increased lipolysis (fat breakdown) and decreased lipogenesis (fat synthesis) which causes free fatty acids (FFA) in the blood
Free fatty acid use
Converted to cholesterol and phospholipids in the blood; breaks down into acetyl-CoA (used by the liver to make acetic acid, which can turn into KETONE BODIES)
Short-term effect of ketone bodies
Causes KETOSIS; short-term increase in serum ketones in the blood and urine that can cause severe metabolic ACIDOSIS and COMA
Long-term effects of ketone bodies
Increased risk of atherosclerosis bc high serum lipid levels