2.4 Fluorescein isothiocyanate (FITC) labeled dextran assay
After 4 hours of fasting, mice were given Chondrex’s Fluorescein isothiocyanate (FITC) labeled dextran (25 mg·kg-1, Woodinville, WA 98072, USA). Maintain fasting conditions and wait 3 hours,collect blood by retro-orbital bleeding, then cillect plasma. Teated according to the related instructions, and settings for reading: excitation: 490 nm/emission: 520 nm.