The pancreas and diabetes Flashcards
What does pancreatic acini produce?
- amylase
- protease
- lipase
- alkaline pancreatic juices
How are these enzymes released into the small intestine?
- travel through pancreatic duct
- released into duodenum (initial segment) assisting in digestion
How can the pancreas act as an endocrine gland?
- use speacalised cell clusters (islets of Langerhans)
- cells within the islets secrete different hormones into the bloodstream
What are the 2 cell types the Islets contain?
Beta cells = secrete hormone insulin
Alpha cells = secrete hormone glucagon
Why is blood glucose regulation vital?
- glucose is essential for cellular respiration
- extreme blood glucose levels can lead to osmotic imbalances in cells potentially causing death
When blood glucose levels increase and insulin is secreted how does this result in lowered blood glucose levels?
1) inhibition of alpha cells reduces glucagon secretion
2) increased glucose uptake (insulin increases permeability of muscle + fat cells to glucose)
3) increased respiration breaking down glucose for energy
4) glycogenesis converting glucose into glycogen for storage (predominantly in liver)
When blood glucose levels decrease and glucagon is secreted how does this result in raised blood glucose levels?
1) inhibition of beta cells lowering insulin secretion
2) reduced respiration decreasing glucose breakdown
3) glycogenolysis converting glycogen in liver and muscle cells back into glucose
4) gluconeogenesis produces glucose from amino acids and fats in the liver
5) adrenaline promoting glycogenolysis and gluconeogenesis in liver + muscle cells
What is the process of insulin secretion from B cells?
1) glucose enters B cells via transporter proteins
2) increased cellular respiration produces more ATP in mitochondria
3) ATP prompts the closure of potassium ion channels
4) this causes an increase in potassium ion concentration inside the cell
5) rise in potassium levels leads to depolarisation, opening calcium ion channels
6) calcium ion influx stimulates insulin release through exocytosis
What are signs and symptoms of diabetes?
- thirst
- frequent urination
- weight loss
- glucose in urine
What are features of type 1 diabetes?
- typically develops in childhood/early adulthood
- leads to no insulin production and high blood glucose levels
- often results from an autoimmune disease destroying insulin producing B cells in the pancreas
What are features of type 2 diabetes?
- occurs when B cells don’t produce enough insulin or the body’s cells resist this insulin
- results in higher than normal blood glucose level
- commonly develops later in life and associated with obesity
What are treatments for type 1 diabetes?
- regular insulin injections
- use of insulin pump providing continuous insulin administrations
- pancreas transplants of healthy islet cells to enable some insulin production
- careful glucose monitoring and a diet balanced with insulin dosages
What are treatments for type 2 diabetes?
- diet control to reduce sugar intake
- regular physical activity
- medications to increase cells sensitivity to insulin
- medications to stimulate more insulin production in cells
- in some cases insulin therapy is necessary
How could stem cells potentially cure diabetes?
- growing stem cells into beta cells
- implanting these B cells into the pancreas of individuals with type 1 diabetes
- allows them to produce their own insulin
What are the benefits of using genetically modified bacteria?
- reduced production costs
- capability to produce insulin in large quantities
- enhanced effectiveness
- lower risk of allergic reaction
- avoids ethical and religious concerns
