6.1 Diabetes

Question 1

What is DMI?

Answer 1

inability to produce insulin

immune-related, or idopathic

Question 2

What is DMII?

Answer 2

inability to respond to insulin

with or without Beta-cell exhaustion

Question 3

What is gestational diabetes?

Answer 3

Glucose intolerance during pregnancy

Question 4

What is diabetes insipidus?

Answer 4

is NOT high blood sugar, but high urine output due to ADH deficiency and is named for excessive production of dilute urine (diabetes = siphon, insipidus = “not tasty”)

Question 5

How does glucose enter the cell?

Answer 5

glucose is a simple sugar (monosaccharide) has to enter the cell through facilitated diffusion (transporter, down concentration gradient, no ATP)
GLUT= glucose transporter

Question 6

What is glycogen? Where is it made?

Answer 6

carbohydrate, a starch made up of many glucose molecules linked together
glucose storage molecule mainly in liver and skeletal muscle
about 12-24 hours of glucose reserve via glycogen

Question 7

How is the liver involved with glucose regulation?

Answer 7

break down glycogen, build up glucose, or store glycogen

Increase blood glucose:
glycogenolysis: breakdown of glycogen to yield glucose
gluconeogenesis: formation of glucose from amino acids (protein breakdown) or glycerol (fat breakdown)
Store glucose as glycogen:
glycogenesis: formation of glycogen by linking glucose molecules together

Question 8

What are 4 stimuli that increase insulin production?

Answer 8

High blood glucose, high amino acids, PNS activation, GI Hormones

Question 9

How does high blood glucose stimulate insulin release?

Answer 9

(ex: after high carbohydrate meal) sensed by the pancreatic Beta cells, directly stimulate insulin secretion
high blood glucose high insulin
low blood glucose  low insulin

Question 10

How do high amino acids stimulate insulin?

Answer 10

(ex: after high protein meal) sensed by the pancreatic Beta cells, directly stimulates insulin secretion

Question 11

How does the PNS stimulate insulin?

Answer 11

parasympathetic activity (Ach) stimulates secretion of insulin
sympathetic nervous system (Epi) inhibits insulin, related to need to mobilize glucose to muscle

Question 12

How do GI hormones stimulate insulin?

Answer 12

“incretins”, stimulate insulin secretion in response to food in GI tract
gastrointestinal insulinotropic peptide (GIP)
glucagon-like peptide (GLP-1)

Question 13

What is the difference between anabolic/catabolic?

Answer 13

Anabolic = storage
Catabolic = breakdown

Question 14

Is insulin anabolic or catabolic? Explain.

Answer 14

storage of nutrients when plentiful (ex: just absorbed after a meal)
increases glycogen formation (glycogen storage), triglyceride formation (fat storage), protein synthesis
decreases fat breakdown (lipolysis), inhibits protein breakdown (proteolysis)
decreases blood glucose, fatty acids, amino acids
lowers blood glucose, lowers amino acids, and lowers fatty acids in the blood
helps cells use and store nutrients

Question 15

What is GLUT-4?

mechanism?

Answer 15

Glucose transporter, essential for bringing glucose into the cell

GLUT 4–>glucose txp molecule –> facilitated diffusion to enter the cell

Question 16

What organs do not need GLUT-4?

Answer 16

Brain, liver

Question 17

What are normal/prediabetes/diabetes fasting blood glucose ranges?

Random plasma glucose?

Answer 17

Normal: 70 to 99 mg/dL
Prediabetes: 100 to 125 mg/dL
Diabetes: 126 mg/dL or higher

Random: >200

Question 18

During a 2-hour plasma glucose trial, what are the ranges for pre-diabetes? Diabetes?

Answer 18

Prediabetes: 140 to 199 mg/dL
Diabetes: 200 mg/dL or higher

Question 19

What are the HbA1C ranges for pre-diabetes/diabetes?

Answer 19

Prediabetes: 5.7% to 6.4%
Diabetes: 6.5% or higher

Question 20

What do the different cells of the pancreas make?

Answer 20

Alpha- Glucagon
Beta- Insulin
Delta- somatostatin (GH)
F-cells- pancreatic polypeptide

Question 21

What hormone(s) lower blood glucose?

Answer 21

ONLY INSULIN

Question 22

What hormone(s) raise blood glucose?

Answer 22

Glucagon, cortisol, GH, epi

Question 23

What are the effects of glucagon?

Answer 23

Increase blood glucose by glycogenolysis (breakdown of glycogen)
Increase fat breakdown
Increase amino acid uptake

Question 24

What causes polydipsia and polyuria in DM?

Answer 24

high glucose raises osmolarity of blood, water leaves cells –> polydipsia
kidneys reach threshold for glucose, excess is eliminated –>glucosuria
excess glucose in kidney tubules pulls water into urine –> polyuria, polydipsia

Question 25

What causes blurred vision in DM?

Answer 25

glucose accumulates in fluid surrounding eyes, alters osmolarity of aqueous fluid, light refraction into eye is changed

Question 26

What causes electrolyte derangement in DM?

Answer 26

water leaving cells can cause dilutional hyponatremia (low blood sodium vs. water)
potassium leaves cells with water: temporary hyperkalemia (high blood potassium), that can mask true hypokalemia (low blood potassium) when potassium returns to cell

Question 27

What causes polyphagia in DM?

Answer 27

body cells are not able to use/take in glucose “starvation amidst plenty”
glycogen pathway is activated higher blood glucose, lipolysis, ketone production

Question 28

What is the mechanism of DKA? In DMI, DMII?

Answer 28

low insulin –> lipolysis –> ketone formation –> decrease blood pH (acidosis)

In DM II can happen when Beta cells are exhausted

Question 29

What is HHS? What causes it? Complications leading to it?

Answer 29

Hyperosmolar hyperglycemia syndrome
Extreme blood glucose 600+ leads to high blood osmolarity. Tx is aggressive rehydration. Complications include ETOH, infection, stress, cocaine