Msmc21b120pk50

Two weeks after injection, MCAO procedures were performed according to previous studies.24 (link) Briefly, mice were anesthetized with 2% isoflurane in oxygen for 3 min and maintained with 1.0 to 1.5% isoflurane in 70% N₂O and 30% O₂ using a small-animal anesthesia system (Vet Equip, Pleasanton, CA, USA). Body temperature was maintained at a constant 37.5 °C during surgery with a heating pad. A midline neck incision was cut and the left common carotid artery (CCA) and external carotid artery (ECA) were isolated. After temporarily blocking the internal carotid artery (ICA) and CCA, a silicone-coated monofilament (MSMC21B120PK50, RWD Life Science Inc., Shenzhen, China) was inserted via the arteriotomy in the ECA and slowly advanced through the left ICA to reach the origin of the middle cerebral artery (MCA). The monofilament was removed after a 60-min occlusion, and the ECA was ligated permanently. Animals that died of anesthetic procedural problems during surgeries, 12h, or had no neurological deficits after the operation were excluded from the study (Supplemental Table 1). The mouse in the sham group was inserted with a monofilament to occlude the MCA and then the monofilament was withdrawn immediately to restore blood flow.

Transient middle cerebral artery occlusion (tMCAO) surgery was performed as described previously (Bu et al., 2021). Briefly, inhalation anesthesia was administered as air containing isoflurane (4% isoflurane within 2–3 minutes for induction, 1.2–1.5% isoflurane for maintenance during surgery, RWD Life Science, Shenzhen, Guangdong Province, China, Cat# R510-22-8), and a heating pad was used to maintain body temperature at 36.5°C. The right common carotid artery, external carotid artery, and internal carotid artery were isolated. Then, an intraluminal filament (coating diameter 0.20–0.21 mm, coating length 3–4 mm, RWD Life Science, Cat# MSMC21B120PK50) was advanced from the external carotid artery stump into the internal carotid artery. One hour after occlusion, mice were re-anesthetized, and the brains were re-perfused by suture withdrawal. Mice then received softened chow and intraperitoneal injection of normal saline for 5 days.