2.2. Animals and treatment

Male Sprague–Dawley rats (180–220 g) were purchased from Beijing HFK Bioscience Co., Ltd and NLRP3 knockout mice were from Jiangsu Aniphe Biolaboratory Inc. Animals were raised in an environment where the temperature was maintained at 19–24°C and the humidity was kept in 40–70% with free access to food and water. Mice were genetically identified before being used in experiments. Rats were used for adaptive feeding for 7 days before experiment. All animal experiments were conducted in accordance with the Guidelines for Animal Protection and Welfare in China and approved by the Animal Care and Use Committee of Zunyi Medical University (Zunyi, China). Rats/mice were injected with 6‐OHDA (15 μg for rats ³² ; 4 μg for mice, ³³ 0.2% ascorbic acid in saline) or LPS (5 μg, in saline) solution into the unilateral substantia nigra in midbrain. Bregma was the origin of the coordinates. Coordinates of rats were 5.2 mm posterior to the bregma, 2.2 mm lateral to the midline, and 8.1 mm ventral to the surface of the skull. Mouse coordinates were 2.2 mm posterior to the bregma, 1.4 mm lateral to the midline, and 4.7 mm ventral to the surface of the skull. ROT (0.5 mg/kg/d) was subcutaneously injected in rats six times a week for consecutive 4 weeks.