Glucose Homeostasis - Lecture 22 Flashcards
What is blood sugar essential for?
Skeletal muscle, CNE, nerves, etc.
Hypoglycemia
Low Blood Sugar
Hyperglycemia
High Blood Sugar
Why is the blood sugar oscilating at around 5 mmol/L
This is the normal blood sugar; tightly controlled with insulin after every meal
At what mmol/L do you see the effects of low glucose levels
2-3mmol/L
What number indicates hyperglycemia?
9mmol/L
Why is staying at 9mmol/L and above bad?
It’s unhealthy for the long term.
How much sugar is circulating in your entire bloodstream?
4g of sugar = 5mmol/L
How much glucose gets oxidized per minute
gram/minute
What lowers blood sugar?
- Insulin Hormone
- Mild to Moderate Exercise
What increases blood sugar?
- Carbs
- Stress (cortisol)
- Growth Hormone
- Glucagon hormone
What should you do after exercise?
Pivot food to eating some carbs
Where do glucagon and insulin come from?
Pancreas
Pancreatic Islet
Found in the pancreas; produces alpha and beta cells
What are alpha and beta cells?
Alpha cells produce glucagon: hormone increasing glucose
Beta cells produce insulin: hormone lowering glucose
Reason for the name Pancreatic Islets?
Looks like an island of cells
Portal Vein?
How insulin and glucagon travel through to the liver
Purpose of Liver
It has receptors that detect glucagon and insulin so it controls glucose homeostasis.
How does Glucagon and Insulin work?
They both work on the liver
How does glucagon get its job done?
It makes the liver release stored glycogen into the bloodstream increasing blood sugar
What does insulin do to the liver?
Makes the liver absorb the glucose from the bloodstream
Does insulin work on other tissues? If so what are they?
Muscles and adipose tissue
How does insulin work on adipose tissue
Similar function to liver where it makes the adipose tissue absorb the glucose.
*What happens to the adipose tissue when they absorb glucose?
Adipose tissue is fat cells so glucose gets converted into fat
*Consequence of glucose being pushed into fat cells all the time?
Having a high carb diet with no exercise means glucose gets pushed into fat cells and get bigger and bigger.
FATTER HUMANS!!
How does insulin play a role with glucose in muscle?
Insulin opens up the muscle to push (absorb) glucose in because glucose is crucial for muscles to work.
Does skeletal muscle respond to glucagon or only liver?
It’s only the liver that responds to glucagon
Summary: What are the three things insulin does to get blood sugar down
Pushes glucose into liver, into adipose tissue and into muscle.
Where is the blood glucose sensor when attached to the body?
The sensor is a small filament that only gets into the subcutaneous tissue (fat that can be pinched).
What is a glucotype
Someone who doesn’t have diabetes but look like they’re at risk
What are the main factors affecting sugar levels
Genes and Environment they live in.
Why do some ethnicities have problems with sugar even though they exercise and manage health?
Insulin sensitivity and capacity to secrete insulin are deficient
How does obesity play a role in glucose levels?
Obesity sets the stage for a disregulated glucose level
Insulin resistance
Muscle and liver does not respond to insulin hormone; common in obese people
What does having a blood sugar of 9 and above for quite a few hours indicative of?
Pre-diabetes or Type 2
What has been seen with the blood sugar levels of athletic people?
Blood sugar goes up with exercise (unknown reason)
Do athletes want Euglycemia, Hypoglycemia or Hyperglycemia when doing a marathon for example?
Euglycemia as insulin levels are low and stress hormones are pumping glucose.
Carbohydrate gut training
Athletes train their guts by exposing it to high amounts of carbs per hour in order to get used to it.
