Disorders of the Endocrine Pancreas, Glucose, & Lipids - End E4 Flashcards
Dr. Swan
What cells of the pancreatic islets produce what?
alpha cells - secrete glucagon
beta cells - secrete insulin
delta cells - secrete somatostatin
When glucose is elevated, insulin is secreted to store glucose. How is this accomplished?
glucose moves in the cells, along with K+ which is a symporter. PO4- also moves in
Which cells uptake glucose through GLUT 4 receptor?
skeletal myocytes
adipocytes
Which cells do not require glucose for uptake? Which receptor?
hepatocytes, neurons, leukocytes, erythrocytes, platelets
GLUT 2 - can take up without insulin stimulus
What does insulin stimulate?
- glucose uptake into cells
- glycogen synthesis
- protein synthesis
- lipid synthesis
- cell growth and gene expression
What do catecholamines do regarding the pancreas, etc?
- act directly on beta islets to inhibit insulin
- act on hepatocytes to break down glycogen
» “fight or flight”: shuttle glucose to necessary tissues - growth-hormone release
What happens when growth hormones inhibits binding of K+ and glucose on GLUT 4?
inhibits effectiveness of insulin
- acromegaly in the cat - diabetes mellitus
How does cortisol act on GLUT 4?
inhibits K+ and glucose binding
- direct effects on liver - produce glucose from other energy sources
- bind to GLUT 4 - inhibit glucose
What are causes of hyperglycemia?
postprandial
diabetes mellitus
pancreatitis
catecholamine excitement
corticosteroid stress
T/F: It is more common to see hyperglycemia in sepsis
FALSE - more common to see hypoglycemia
Describe the characteristics of diabetes mellitus in dogs
females
smaller breeds
type 1 diabetes
Which form of diabetes mellitus in canines is more common?
type I
What happens with type I diabetes mellitus in dogs?
- lymphocytic infiltration into islets and destroys them
- chronic pancreatitis
perform cPL
What does canine diabetes mellitus look like on chemistry?
marked hyperglycemia
titrational metabolic acidosis
- hypercholesterolemia - mobilization of fat as alternative energy source
- hypertriglyceridemia: same
- increased ALT
- inclreased ALP
What does canine diabetes mellitus appear on UA?
USG < 1.025
- glucosuria
- +/- ketonuria
- aciduria
UTIS
In diabetes mellitus in dogs, what accumulate between the lens proteins resulting in cloudiness (cataracts)?
sorbitol
What type of diabetes mellitus is more common in cats?
type II - insulin resistance or defects in insulin secretion
older, obese cats
What are clinical signs of feline diabetes mellitus?
type 2
What does feline diabetes mellitus look like on chemistry?
marked hyperglycemia
titrational metabolic acidosis
- hypercholesterolemia - mobilization of fat as alternative energy source
- hypertriglyceridemia: same
What does feline diabetes mellitus appear on UA?
USG < 1.025
- glucosuria
- +/- ketonuria
- aciduria
UTIS
What stances can cats do with diabetes mellitus?
- cervicoventral flexion (like hyperaldosteronism)
- plantigrade stance
What are the components of diabetic ketoacidosis?
- diabetes mellitus
- titrational metabolic acidosis (increased anion gap)
- aciduria
- ketonuria or ketonemia
What are the characteristics of a hyperosmolar hyperglycemic states?
diabetes mellitus with
- severe hyperglycemia
- high serum osmolality
- profound dehydration
- alkaline pH
- high bicarb
- small to absent ketonuria
- altered consciousness
List the osmolality in cats, dogs, and horses
dogs: 290=310
cats: 290-330
horses: 280-320
How do you calculate osmolality?
How do you diagnose diabetes mellitus in both cats and dogs?
based on clinical signs, PE findings, clinicopathologic abnormalities, and the demonstration of a persistent fasting-marked hyperglycemia and glucosuria
What are the diagnostic assays for diabetes mellitus?
- serial elevations in blood glucose with glucosuria and ketonuria
- fructosamine
How does fructosamine diagnose diabetes mellitus?
- indicative of long-term hyperglycemia when elevated
- favored in CATS to differentiate between glucocorticoid stress effects (transient) and diabetes mellitus (persistent)
What are some causes of hypoglycemia?
iatrogenic: prolonged contact with red blood cells prior to spinning - glucose is metabolized as energy for red blood cells
insulinoma, non-B cell metaplasia
xylitol
What are the two major serum lipids?
- cholesterol
- triglycerides
Where is cholesterol found in the highest amounts?
hepatocytes
enterocytes
(in all cells but in highest amounts here)
Look at the causes of hypercholesterolemia
Look at the causes of hypocholesterolemia
Look at the causes of hypertriglyceridemia
T/F: Hypotriglyceridemia has no significant pathologic states that have been identified in animals
TRUE
