Figure 4. SP induces microglial migration in a trans-well system through a NK1R-dependent manner.
(A) SP-induced microglial migration was assessed in a 96-well cell migration system with 5 μm pore size using purified microglia. Different concentrations of SP (10−13 to 10−6 M) were placed in the bottom wells, and the number of microglia that migrated over the 4-hour incubation period was determined. fMLP (10−8 M) was served as a positive control. Data are expressed as mean ± SEM. (B) Microglia were pre-treated with NK1R antagonist CP-96, 345 or L-703, 606 for 30 mins and followed by chemotaxis assay induced by 10−8 M SP. The number of migrated microglia was determined. (C) Purified microglia were prepared from WT and NK1R−/− mice. The chemotaxis capacity of SP on WT and NK1R−/− microglia was assessed. Results are expressed as the migration index (mean ± SEM). *p< 0.05, **p< 0.01. n = 4–5.