Fig. 5

Effects of HR antagonists on HA-induced stimulation of GDNF protein levels in astrocytes. a Incubation with histamine at the doses of 0.01 and 0.1 μg/ml for 6 and 24 h significantly promoted GDNF expression in astrocytes. b Astrocyte cells were stimulated with histamine (0.1 μg/ml) in the absence or presence of the H1R antagonist cetirizine (10 μM), the H2R antagonist ranitidine (10 μM), and the H3R antagonist carcinine (10 μM) added 30 min before stimulation. At 24 h after the addition of histamine, levels of GDNF were detected by Western blotting, quantified, and normalized to GAPDH levels. Values are expressed relative to the control, which was set to 1. **p < 0.01 versus the control group. ^#p < 0.05, ^##p < 0.01 versus histamine (0.1 μg/ml) treatment groups. The data are presented as the mean ± s.e.m. of three independent experiments. c The astrocyte cells were stained with anti-GDNF antibody. Expression of GDNF (green) in activated astrocytes was visualized by confocal microscopy. The blue staining represents DAPI. Scale bar = 25 μm