Diabetes

Question 1

Diabetes definition

Answer 1

• “to pass through”

- Diabetes = name given to 2 very dif diseases that are characterised by the passing of large quantities of urine

Question 2

Diabetes mellitus

Answer 2

• high blood glucose levels, filtered at glomerulus
• high [glucose] in filtrate
• glucose (R) symports (SGLT) are overwhelmed + cannot transport all glucose
  some glucose remains in TF
• The glucose that remains in the TF draws water to it because of osmosis
  = ↓ osmotic gradient → water is kept in TF
  = high urine vol w/ high glucose concen.

Question 3

renal threshold for glucose

Answer 3

• renal threshold for glucose is 160-180 mg/100ml

- normal blood glucose is ~70-110mg/100ml

Question 4

Diabetes Insipidus (DI): definitions + type

Answer 4

• A hormonal disease that is also characterised by high urine output, but the cause is totally dif to diabetes mellitus
  Types:
• neurogenic: deficiency of vasopressin production (antidiuretic hormone, ADH)
• nephrogenic: insensitivity of kidneys to vasopressin

Question 5

Diabetes Insipidus (DI): in depth

Answer 5

• Vasopressin normally acts at CD to increase water (R)
• With no vasopressin, there is significantly less (R) of water by nephron (collecting duct) → increase urine production.

Symptoms & signs:

• high urine output, no glucose in urine
• urine volumes up to 24 litres/day
• excessive thirst!

vasopressin = regulated by pituitary gland