Collagenase-Induced Striatal Injury Model

For ICH, animals were anesthetized with isoflurane (graded induction to 4%, 2%-3% maintenance) and placed in a stereotaxic frame.^{45 (link)} A midline incision was made over the scalp to expose the surface of the skull and a burr hole was made 0.5 mm anterior and 3.5 mm lateral to Bregma,^{46 (link),47} contralateral to the dominant paw (established during baseline reach testing). An infusion of 1.2 μL of 0.6 U bacterial collagenase (Type IV-S, Sigma) was injected 6.5 mm deep into the striatum over 5 minutes (26-gauge Hamilton syringe). The syringe remained in place for an additional 5 minutes to prevent backflow. The burr hole was then sealed with a small screw, and the scalp was closed. Temperature was monitored throughout the procedure via rectal probe and maintained at 37°C ± 0.5°C via heating pad. All animals received Marcaine (0.5 mL S.C., Pfizer Canada) for pain management at the incision site. Rats were provided with a wet mashed rat chow following surgery and recovery was monitored through daily weighing and health checks.