Endothelin

Nystatin, angiotensin II, vasopressin, endothelin, heptanol 18BGRA, collagenase 1A, protease XIV and other chemicals were from Sigma (St Louis, MO). Reagents were thawed and diluted on the day of the experiment and excess discarded daily.

Before ischemia, a healthy male Macaca Mulatta of 19 years old was anaesthetized by ketamine for anesthesia induction and pentobarbital sodium for anesthesia maintenance. Then, T1 and T2 MRI scanning were performed on both left and right motor cortex. According to the localization of MRI scanning, endothelin (Cat: E7764, Sigma, 5 ug/ul) was injected into 3 points of one side motor cortex with intervals of 5 mm (5 μl per point, 4 mm in depth) to induce ischemia. At 24 h post ischemia, the monkey was perfused through heart by 4% paraformaldehyde phosphate buffer (PFA, Cat: P0099, Beyotime). The brain tissue was dissected immediately after perfusion and post-fixed by 4% PFA for about 2 h. All the procedure and protocol of monkey experiments were performed under the approval of the Animal Care and Use Committees of Kunming Institute of Zoology, Chinese Academy of Sciences (animal ethic review number: IACUC19009).