Novel object recognition test
7 days after LPS treatment, the novel object recognition test (NORT) was applied to examine cognitive function in mice(W. Zhang et al., 2020). Mice were handled 6 days before the test, for 1 minute a day. Then, putting mice into the box for 5 minutes to acclimatization. 24 hours later, mice were allowed to explore two identical rectangular blocks for 5 minutes. After 2 hours, a cylinder was used to replace one of the rectangular blocks, and mice explored for another 5 minutes. Exploratory behaviors were performed as sniff, lick and climb. Discrimination ratio was used to assess learning and memory.