Diabetes - patho Flashcards
What is the main energy source for cell function
glucose
Why is insulin needed
to help glucose cross over the plasma membrane
What are the islets of langerhans
tissue in the pancreas that produces insulin
Action of insulin
lowers blood glucose through increased uptake of glucose into the cell, promotes gluconeogenesis
Action of glucagon
raises blood glucose by promoting glycogenolysis
Action of somatostatin
inhibits insulin and glucagon to prevent fluctuations of blood glucose levels
Diabetes
a disorder of carbohydrate metabolism characterized by high levels of blood glucose resulting from the body’s inability to produce or utilize insulin
Type 1 diabetes
the body does not produce insulin
Type 2 diabetes
the body is resistant to insulin
How does type 1 diabetes occur
T-cell mediated autoimmune destruction of the insulin-secreting beta cells
When is type 1 diabetes usually diagnosed
in kids or young adults
How does type 2 diabetes occur
insensitivity of body cells to insulin due to down-regulation of the pancreas
the pancreas was working overtime to secrete extra insulin to bring blood sugar down
What cells are the most resistant to insulin
fat cells
How does gestational diabetes occur
Hormonal changes make the cells less responsive to insulin
What can untreated gestational diabetes lead to
fetal defects, premature delivery, hypoglycemia in newborn, heavy birth weight
How does hyperglycemia in a mother affect a fetus
the extra glucose gets into the baby’s bloodstream and causes the baby’s pancreas to work harder to produce more insulin
What general type of injury is caused by chronic hyperglycemia
endothelial injury
How does endothelial injury lead to the hardening and narrowing of blood vessels
inflammatory response, lipid and macrophage deposition
Gluconeogenesis
breakdown of amino acids and fats to convert to glucose
Glucogenolysis
breakdown of stored glycogen to get glucose
Somogyi effect
blood sugar drops at night (hypo) –> hormone response to raise glucose levels –> high blood sugar in the morning (hyper)
Does the somogyi effect occur in type 1 or type 2 diabetes
Type 1
What is the cause of the somogyi effect
having extra insulin in the body at bedtime
Dawn phenomenon
growth hormone, epinephrine, and cortisol cause a release of large amounts of glucose into the blood stream causing hyperglycemia in the morning
What should blood glucose levels and A1C levels be maintained at
70-140, <7%
What is used to help control blood glucose when lifestyle changes are not adequate (in type 2)
metformin
How does metformin work (class: biguanide)
acts as an insulin sensitizer to make the body tissues less resistant to endogenous insulin, inhibits hepatic synthesis of glucose
Fasting plasma glucose test (FPG)
nothing to eat or drink for 8 hours, result of 126 x2 confirms
A1C-glycated hemoglobin
diagnose and monitor control over a 3 month period
Oral glucose tolerance test (OGTT)
ingests a specific amount of carbs, glucose is checked 2 hours later, greater than 200=diabetes
Islet cell antibody test
presence of antibodies indicates type 1 diabetes
C-peptide test
c-peptides are released when the pancreas produces insulin, type 2 diagnosis
Glucosuria
extra glucose excreted in the urine
ketonuria
presence of ketones in the urine reveals prolonged/uncontrolled diabetes
