Diabetes Flashcards
What is the role of ATP potassium channels in other physiological and pathophysiological conditions?
- Glucose dependent insulin release
- Vascular smooth muscle tone
- Glucose sensors in the brain
- Muscle fatigue
- Protective during ischemia
- Ischemic preconditioning
What is an example of thiazolendiones and how does it work?
- Pioglitazone
Sensitise peripheral tissue to insulin
MOA: agonist for PPAR-gamma which upregulates IRS1, IRS2, PI3K, GLUT4
Taken once daily with or without food
SE: increased risk of bladder cancer and cardiovascular events, drug induced hepatitis
What is the target for diabetic patients?
- Pre-meal: 4-7mmol/L
2. Post meal: <10mmol/L
What is an example of biguanides and how does it work?
- Metformin - OBESE
- Decreases hepatic glucose production
- No effect on insulin secretion
- enhances peripheral glucose uptake by phosphorylating GLUT4 enhancer factor
- decreases glucose absorption in the GI tract
Pharmacokinetics: not metabolised, cleared by kidneys
Available in different forms:
- tablets for immediate release (up to three times per day) or prolonged release (usually once per day)
- oral solution and powder for oral solution for immediate release
Contraindications: renal failure and heart failure
Why do you get hypokalemia in diabetes?
- sodium and potassium in urine due to high glucose conc in urine
What are the adverse effects of insulin therapy?
- Hypoglycaemia
- Weight gain
- Lipoatrophy
- Lipohypertrophy
- G < 3.5mmol - adrenergic symptoms
G < 2.5mmol - neuroglycopaenic (brain affected)
What are some sulphonylureas and how do they work?
NON-OBESE
- Tolbutamine
- Glibenclamide - high affinity for beta cells
MOA:
close beta cell K-ATP channel
:. depolarisation occurs
:. Influx of calcium
:. Release of insulin
SE:
weight gain
Hypoglycaemia
Could affect other cells which have potassium channels such as cardiac muscle and SM
How does insulin therapy work?
- 0.5units/kg/day
Twice daily regimen:
- Short acting insulin x2
- Intermediate acting insulin x2
Four times daily regimen:
- 3 times short acting
- Intermediate acting at night
Route:
- subcutaneous for normal therapy
- IV for DKA or surgery
What is gastroparesis?
When the muscles of the stomach do not work properly to grind the food
