2.3 Intraventricular injection
SD rats were fixed on a brain stereoscope, the skin was cut at the top of the head (1.5-2 cm), the periosteum was carefully peeled off, and the fontanel and posterior fontanel were fully exposed, with the fontanel as the coordinate zero point (0.5 mm on the posterior side, 1.5 mm on the right side, 4.5 mm in depth). The skull was drilled, and the cerebrospinal fluid was pumped back with a microsyringe to determine the correctness of the location (S. Li et al., 2021). NSC-Exos group was injected with NSC-Exos suspension 20 μl (30 μg) in the lateral ventricle, and PBS group was injected with Phosphate buffer saline (PBS) of the same volume. TAK-242 (Sigma-Aldrich) was dissolved in 10% Dimethyl sulfoxide (DMSO, Sigma-Aldrich) by injection of 1.2 mg/20μl into the lateral ventricle (Feng et al., 2017; Hua et al., 2015). All injections were performed at the rate of 2.0 μl/min, and the needles were retained for 10 min and then slowly withdrawn (L. Wang et al., 2020).