2. Diabetes is diagnosed when a person has
too much glucose (sugar) in the blood.
This happens because the pancreas cannot
make enough insulin.
Insulin is produced in the pancreas and has two
jobs in the body - the first is to transport glucose
from the blood supply into fat and muscle cells,
where it can be used for energy. The second is to
switch off the liver once the level of glucose in
the blood is high enough. Diabetes is the result
of the body not creating enough insulin to keep
blood glucose levels in the normal range.
7. 6
(1) Alloxan induced diabetes:-
Purpose –
Induction of diabetes using chemical alloxan.
In most species, triphasic time course is observed.
(Initial rise of glucose is followed by decrease, again
followed by sustain increase of blood glucose).
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14. 13
Procedure
Male Wistar Rat- 150-200 gm
Group- Test, Standard, Control
STZ. Dose- 60 mg/kg iv or ip
Done in mice (175-200 mg/kg i.p. or i.v.) and dogs
(15 mg/kg for 3 days)
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18. Viral induced
17
Principle
D-variant of Encephalomyocarditis virus (EMC-D)
selectively infects and destroys pancreatic β-cell.
elevation of islet cell antibody, and prolonged
presence of viral RNA in the pancreas.
Associated with chronic islet cell inflammation,
Others: RNA picornavirus, Coxsackie virus
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19. Surgical induced
18
Partial pancreatectomy: usually anterior lobe is left
intact
Disadvantages
Loss of α cells (glucagon and somatostatin loss)
Loss of pancreatic enzymes (creates digestive
problems)
Difficult to achieve
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21. BB Rat
A model of spontaneous diabetes
associated with insulin deficiency due
to autoimmune destruction of β cells
Bio Breeding
rat
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22. NOD Mice
•Develop diabetes
between 100 and 200
days of age.
Non-Obese Diabetic
mice
•As well as rapid weight
loss, polyuria, and
severe glucosuria.
• Caused by specific T-
cell mediated
destruction of β cells
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23. NIDDM
i)
Chemical
22
Neonatal streptozocin model
Species: Rats (Wistar or Sprague-Dawley)
Effect: Initial rise in plasma glucose and becomes
normoglycemic by 3 weeks of age
Others: Adrenaline in rabbits
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24. 23
Procedure:
STZ (80-100mg/kg/i.p.) given at birth or within 5
days
Severe β cell destruction
Reduction in insulin stores and raised glucose levels
β cells of neonates partially regenerate (in contrast to
adult rats)
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25. Transgenic techniques
A transgenic animal is one that carries a foreign gene that
has been deliberately inserted into its genome.
takes place.
Transgenesis is the process by which mixing up of genes
Foreign genes are inserted into the germ line of the
animal, so it can be transmitted to the progeny.
Use : for creating animal models of diabetes
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26. 25
Transgene made of 3 parts:
Promoter
Gene to be expressed
Termination sequence
Introduction of foreign gene into the animal
Embryonic stem cell method
Pronuclear microinjection method
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