To begin, place the anesthetized mouse on an absorbent pad or diaper. Pinch the mouse toe to confirm the ceased reflexes. Using surgical tape, secure all limbs with the chest cavity facing upward.
Employing tweezers and scissors, carefully open the chest cavity to expose the heart. Insert a 23 gauge blunt needle into the left ventricle of the heart for perfusion. Then mix five milliliters of silicone rubber compound solution, with five milliliters of the diluent in a 50 milliliter tube.
Using a hose linked 23 gauge blunt needle, inject 10 milliliters of the mixed compound into the heart. Next day using fine tweezers, gently remove the skull of the mouse and place the extracted brain in 4%paraformaldehyde at room temperature. After a 24 hour incubation, wash the brain three times in PBS and store it in 30%sucrose at four degrees Celsius.
Pictographs of brains illustrated the enlargement of the basala artery and increased tortuosity around the circle of Willis following elastase injection compared with the PBS control group. Compared to the control group treated with PBS a significant blood vessel dilation was observed following a single elastase injection into the cisterna magna of three month old mice, which sustained for three months.
