1. Regulating blood sugar
© 2016 Paul Billiet ODWS

2. The Pancreas © 2016 Paul Billiet ODWS
© 2016 Paul Billiet ODWS

3. Anatomy The pancreas is an exocrine gland
secreting alkaline digestive juices
into the duodenum via the pancreatic duct
The pancreas is also an endocrine gland
the endocrine cells are in the Islets of Langerhans
© 2016 Paul Billiet ODWS

4. Islets of Langerhans
An oval collection of cells scattered through the pancreas
1 to 2 million islets in a human pancreas
Islets are darker red than the surrounding tissue having a rich blood supply
The blood from the islets drains into the Hepatic Portal Vein going directly to the liver
© 2016 Paul Billiet ODWS

5. Hormone secreting cells
 cells secrete glucagon
 cells secrete insulin
© 2016 Paul Billiet ODWS

6. Hormone action (t½ = 10 to 25 min) (t½ = 5 to 10 min)
Action of Insulin
Action of Glucagon
Increases glucose uptake into body cells
Inhibits glycogen breakdown in liver and muscle
Glucagon binds to liver cells, stimulating the breakdown of glycogen into glucose
Acts quickly and is broken down quickly
(t½ = 10 to 25 min)
(t½ = 5 to 10 min)
© 2016 Paul Billiet ODWS

7. Control of Insulin Secretion Control of Glucagon Secretion
Stimulating chemicals in the plasma
These include: Glucose, amino acids, glucagon.
Glucagon levels rise between meals as the glucose and fatty acid levels in the blood fall
In many ways it is antagonistic to insulin.
© 2016 Paul Billiet ODWS

8. Normal blood glucose concentration
Summary
INSULIN
Normal blood glucose concentration
GLUCAGON
© 2016 Paul Billiet ODWS

9. INSULIN DEFICIENCY: Diabetes mellitus
Symptoms
Hyperglycaemia (high blood glucose)
Glucosuria (glucose in the urine)
Polyuria (passage of copious urine)
Polydipsia (drinking large amounts)
Increased appetite
Weight loss
Acids and ketones in the blood from lipid breakdown (toxic)
Coma if ketones build up.
© 2016 Paul Billiet ODWS

10. “STARVATION IN THE MIDST OF PLENTY”
Diabetes
Diabetes is sometimes described as:
“STARVATION IN THE MIDST OF PLENTY”
There is plenty of glucose circulating in the blood but it cannot get into the cells that need it
Treatment
Intravenous or oral doses of insulin at regular intervals
Strict diet and meal times.
© 2016 Paul Billiet ODWS

11. Types of diabetes Type 1 Aka “Juvenile” Type 2 Aka “adult-onset”
β-cells no longer make insulin
Insulin made normally but the body cells do not respond to it
Islet cells destroyed by the immune system (auto-immune disease)
More insulin is secreted to compensate
Eventually the islet cells cannot keep up with the demand
© 2016 Paul Billiet ODWS

12. Types of diabetes Type 1 Type 2 Thought to be genetic in origin
Associated with obesity and inactivity
May be triggered by childhood infection (e.g. mumps)
Obesity also has a genetic predisposition
Today more and more young people suffer from Type 2
© 2016 Paul Billiet ODWS

13. Gestational diabetes Similar to Type 2 Develops during pregnancy
Placental hormones interact with insulin secretion
Women who develop it seem to have a genetic predisposition
© 2016 Paul Billiet ODWS

14. Increasing numbers of diabetics
Life style (exercise, snacking)
Change of diet (refined sugar, saturated fats)
Migration and change of diet
Ethnic differences (US: Caucasians 6%, Afro/Asiatic Americans 10%, Native Americans 20-50%)
© 2016 Paul Billiet ODWS