**11. Collagenase induced brain hemorrhage model**

This method is widely used in understanding the extent of hemorrhage in the brain and mimics the condition of human stroke. In this model, Sprague–Dawley rats are used. Animals will be anaesthetized using 50 mg/kg of pentobarbitol. Once the animals are anaesthetized, they are placed in stereotactic equipment, and a 23-gauge needle will be used to implant the caudate nucleus. Rats will be infused with 2 μl of saline containing (Type VII or Type XI collagenase) for 9 min. After completing the infusion process, the needle is removed, and the wound would be sutured. Rats will be allowed for recovery than will be sacrificed using an intracardiac injection of KCl (Potassium chloride). Brains of the rats will be removed and kept in phosphate-buffered formalin for 24 hours. Later, brains will be sliced, and histopathological changes will be studied [75].

Merits of Collagenase induced brain haemorrhage model [76].


Demerits of Collagenase induced brain hemorrhage model [76].

