Hormones Controlling Plasma Nutrients Flashcards
(36 cards)
What tissues does insulin cause glucose to go into?
Skeletal muscle, the liver and adipocytes
How does insulin reduce the hepatic glucose output?
By stimulating glycogen synthesis and inhibiting glycogenolysis (the breakdown of glycogen)
What does insulin do the the amino acids in the plasma?
Stimulates their incorportation into proteins in the muscle and fatty acids in the liver
What does insulin causing increased uptake of amino acids and glucose by the liver lead to?
Conversion to fatty acids and then to lipoproteins which are released into the blood
Where do the lipoproteins go once released into the blood? What action causes this?
To adipocytes through lipoprotein lipase action
What does insulin cause glucose oxidation to?
Fatty acids which are stored as triglycerides (lypolysis prevented)
What are the three long term effects caused by insulin
- Fatty acids into adipocyte store
- Glucose into glycogen or adipocyte fat
- Amino acids into protein or fatty acids
What cells have the receptors to sense glucose changes?
B-cells in the pancreatic islets
What happens to stimulate insulin secretion from the B-cells in the pancreatic islets
Calcium ions rush into the cell causing insulin release
What does oral glucose do to change insulin levels?
Effects the levels via GIP
What does a rise in amino acids do?
Increases release
What does the sympathetic nervous system do the insulin secretion?
Inhibits it
What does the parasympathetic nervous system do the insulin secretion?
Increase it
What does somatostatin do the insulin secretion?
Inhibits it
What does a rise in glucagon levels do the insulin secretion?
Stimulate the release
What are ketone bodies?
They are produced from the liver during prolonged fasting
What do ketone bodies do to insulin secretion?
They stimulate it
Where is glucagon secreted from?
alpha-cells in the islets
What are the four action of glucagon?
- Adipocyte lipolysis
- Liver gluconegogenesis
- Liver glycogenolysis
- Liver ketone synthesis
What does adipocyte lipolysis by glucagon cause?
Fatty acids and glycerol production
What does liver gluconeogenesis and glyconeogensis cause?
The breakdown of proteins and glycogen into glucose
What are ketones?
Small molecules derived from fatty acids that will enter the TCA when proteins are broken down
What does insulin do to glucagon release?
Inhibits it
What does low blood glucose levels do to glucagon release?
Stimulates it
