Mouse Models of Intracerebral Hemorrhage

As we previously reported, ICH was induced in mice by injection of autologous blood or bacterial collagenase (Li et al., 2017a (link),b (link); Ren et al., 2018 (link)). First, mice were anesthetized with an intraperitoneal injection of ketamine (100 mg/kg) and xylazine (10 mg/kg). After placing the mice on a stereotactic frame, a 1-mm burr hole was drilled on the right side of the skull (2.3 mm lateral to the midline, 0.5 mm anterior to the bregma). For the collagenase ICH model, 0.0375U bacterial collagenase (Type IV-S, Sigma, St. Louis, MO, USA) dissolved in 0.5 μl saline was infused at the caudate nucleus (3.7 mm depth beneath the skull) through an infusion pump (Kd Scientific Inc., Holliston, MA, USA) at a rate of 0.5 μl/min. In some experiments, we induced the mouse ICH model by infusion of autologous blood using a double-injection method. Whole blood (30 μl) was withdrawn from the angular vein and then infused into the brain as previously described (Sun et al., 2016 (link)). 5 μl of blood was first injected to generate a clot at a depth of 3 mm beneath the hole. Then the needle was moved to a depth of 3.5 mm to inject the remaining 25 μl of blood at the rate of 1 μl/min. After surgery, animals were placed in cages and provided with free access to food and water.