Download pancreas and diabetes

PANCREAS AND DIABETES
Valerija Vrhovnik
Mentor: A. Žmegač Horvat
Anatomy of pancreas
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head
body
tail
acinar cells
islets of Langerhans
pancreatic duct
Pancreas: dual-function gland
• Exocrine pancreas (acinar cells):
• produces digestive enzymes (trypsin,
chymotrypsin, pancreatic lipase and amylase )
• enzymes help further breakdown of
carbohydrates, proteins, and fat
Endocrine pancreas
• Islets of Langerhans
4 types of cells:
1) Alpha cells – produce glucagon (hormone);
25% total cells
2) Beta cells – insulin synthesis and
secretion; 60%
3) Delta cells – produce somatostatin (inhibits
secretion of other hormones); 10%
4) PP cells – secrete pancreatic
polypeptide; <5%
Insulin = hormone of feasting
• small protein composed of
two peptide chains
Insulin effect on metabolism
• 1) Carbohydrates: ↑ glucose utilization, ↑
CHO storage, use of CHO for energy
• 2) Fats: ↓ use of fat, fat sparer
• 3) Proteins: ↑ protein anabolism, inhibits
catabolism
Factors Regulating Insulin
Secretion
1) High plasma glucose levels –
insulin secreted to return glucose
levels back to normal
2) High plasma amino acids – after a
high protein meal, arginine and lysine
stimulate beta cells to increase insulin
secretion
3) Fatty acids and ketone bodies –
increases secretion
Diabetes mellitus
• Type 1 – juvenile
diabetes:
• loss of insulin-producing beta
cells leading to a deficiency of
insulin
• Type 2 – maturity onset:
• insulin resistance - cells fail to
use insulin properly
• the most common type
Causes:
• heredity - stronger inheritance
pattern for type 2
• type 1 appears to be triggered by
some (mainly viral) infections
(e.g. Coxackie virus)
• obesity – type 2
Symptoms:
1) Polyuria (excess
urine production)
2) Polydipsia
(excess drinking of
water)
3) Polyphagia
(excessive eating)
4) Loss of weight
5) Asthenia (lack of
energy)
Complications:
• Diabetic cardiomyopathy
• Diabetic nephropathy
• Diabetic neuropathy
• Diabetic foot
• Diabetic retinopathy
Treatment:
• Diabetes type I:
• artificial insulin – subcutaneous injection
• insulin control, diet, weight control and exercise
• Diabetes type II:
• diet, weight loss
• exercise to increase receptor responsiveness
• sulfonylureas to increase number of receptors