4.4. Establishment of Middle Cerebral Artery Occlusion (MCAO) Rat Model

Middle cerebral artery occlusion (MCAO), a commonly used I/R model, was established to evaluate the pharmacodymics of ginsenosides [44]. After fasted for 12 h, SD rats (250 ± 10 g) were injected intraperitoneally with 10% chloral hydrate (4 mL/kg), and then fixed in supine position. The skin was cut on the neck along the line, and the submandibular gland was separated to expose neck vessels. The left common carotid artery (CCA), external carotid artery (ECA) and internal carotid artery (ICA) were unilaterally separated. After CCA and ECA were ligated, ICA was clamped and a small hole was cut on it. A monofilament nylon thread coated with poly-L-lysine was inserted into the ICA through the hole, and push forward about 18–19 mm to the starting point of the middle cerebral artery (MCA) to fix the nylon thread. After 1.5 h of ischemia, the nylon suture was removed to enforce reperfusion. Then, the skin was sutured and 1 mL of physiological saline was intraperitoneally injected. The body temperature of the rats was maintained at 37.5 °C ± 0.5 °C with a heating pad during the whole process of surgery and ischemia.