Figure 6.

Close proximity between GAL₁ and GAL₂ receptors and their effects in 5-HT synthesis and storage in RN33B cells. (A) Detection of close proximity between GAL₁ and GAL₂ receptors (seen as red clusters indicated by arrows) in RN33B cells by in situ proximity ligation assay; nuclei are shown in blue (6-diamidino-2-phenylindole). (B) Quantification of 5-HT immunoreactivity (green color) was used as a marker for 5-HT synthesis and storage in RN33B cell cultures after incubation with GAL29 and GAL(1–15). RN33B brain-derived immortalized cells were treated for 1h with GAL29 (100nM), GAL(1–15) (100nM), or control, followed for 1h by recuperation. 5-HT immunoreactivity was determined after immunofluorescent labeling. The data are presented as mean ± standard error of the mean, n = 60 cells for two independent experiments. ***p < 0.001 vs. control according to one-way analyses of variance followed by Newman Keuls Multiple Comparison Tests. (C) Representative images of 5-HT stained RN33B cells under different conditions are presented. Scale bars, 10 μm.