Animals
All experimental protocols were approved by the Institutional Animal
Care and Use Committee of the Qingdao University. Male Sprague-Dawley
rats weighing 260–280 g were purchased from Vital River Laboratory
Animal Technology Co. Ltd (Beijing, China). The animals were maintained
in standard‐housing open‐top cages at a specific pathogen-free facility
at 23 ± 1°C with 50%–60% humidity at Qingdao University. Before the
procedure, all animals were fasted for 24 h with free access to tap
water.