Insulin Tolerance Test

Materials (Bring Downstairs)

Glucometer - AccuChek Advantage
Glucose Test Strips - AccuChek Comfort Curve. Order these through Materiels Service by calling 936-6077 and ordering product 2535. For information see [here]
Scale
Beaker for weighing mice
Syringes
0.1 U/mL humulin in PBS (make as 10uL of 100 U/mL in 10 mL, sterile filtered). This will correspond to 1 U/kg injections. This may need to be adjusted depending on the insulin sensitivity of the mice. This is diluted from Humulin R-100 and is purchased through the veterinary staff.
Timer

Remove food from mice for about 6h. Add do not feed tag to cages, or move cage to procedure room.
Typically starve the mice at 9AM and aim to start injections at 3 PM
Weigh mice, mark tails if necessary and take fasting glucose measurement via a tail clip.
Prepare glucose syringes with 10 uL per g mouse weight (ie for a 30g mouse, 300 uL).
At approximately 1 min intervals, inject appropriate amount of insulin into interperitoneal cavity of the mouse.
- Immobilize mouse and restrain tail with one hand
- Aim needle between the midline and the hip bone
- Insert syringe (do not inject) into cavity
- Eject syringe.
At desired intervals (normally 15, 30, 45, 60, 75, 90, 105 and 120 min), take blood glucose measurements from tail vein. If needed re-snip the tail vein. When measuring glucose just lift the tail of the mouse, while leaving it in the cage, rather than removing and restraining the mouse.
Analyse data by both % change from fasting glucose and absolute values