1.4 - insulin and diabetes Flashcards
What is the role of insulin?
To maintain constant blood glucose levels which must be kept within strict limits.
What causes the production of insulin.
Pancreatic cells detect a rise in blood glucose level and produce insulin.
Why is insulin important?
It allows fat tissue and skeletal muscles to absorb glucose.
How does glucose enter the cell?
By facilitated diffusion
Describe how insulin works…
Binding of insulin to receptor results in intracellular signalling cascade which triggers GLUT4 recruitment to fat and muscle cell membranes.
Insulin binding causes conformational change that triggers phosphorylation of receptor; starts phosphorylation cascade within cell eventually leading to vesicles containing GLUT4 being transported to cell membrane.
How is diabetes caused?
A failure at a point in the insulin pathway.
What causes type 1 diabetes?
Caused by insulin production failure in pancreas.
What causes type 2 diabetes?
loss of insulin receptor function; associated with obesity.
How is type 1 diabetes treated?
It is treated with regular insulin injections throughout day and healthy diet.
How is type 2 diabetes treated?
it may be treated with medication to lower blood glucose levels as well as lifestyle changes, less sugar consumption and increased activity levels.
What can exercise do for blood glucose levels?
Exercise also triggers GLUT4 recruitment so improves glucose uptake in fat and muslce cells in subjects with type 2 diabetes.
