Figure 6

HTR2c agonist prevents the increase of adult hippocampal neurogenesis in hTM-DTA^iPet1 mice.

(a) Scheme of combinatorial injection of tamoxifen and 5-HTR agonists in mice. Tamoxifen was injected on day 1, 2, 4 and 5, while agonists was from day 3 to day 26. (b) Representative figures of DCX⁺ cells in control mice and hTM-DTA^iPet1 mice treated with different agonists. (c) Quantification of DCX⁺ cells in control and hTM-DTA^iPet1 mice treated with different agonists. Numbers of DCX⁺ cells in hTM-DTA^iPet1 mice were normalized to those of control mice and expressed as DCX increase index. 5-HTR1a and 5-HTR2 family agonists have no apparent effects on the increase of DCX⁺ cells, but 5-HTR2c agonist partially blocks this increase in hTM-DTA^iPet1 mice. Data were compared using one-way ANOVA (alpha = 0.05) with post hoc Tukey test (p = 0.011 for comparison of vehicle and 5-HTR2c agonist). (d) Scheme of combinatorial injection of tamoxifen, 5-HTR agonists and BrdU in mice. (e) After injection of 5-HTR2c agonist, the increase of BrdU⁺ cells in hTM-DTA^iPet1 mice is prevented. (f,g) Quantification of BrdU⁺ cells and DCX⁺ cells. There is no significant differences between control and hTM-DTA^iPet1 mice in number of BrdU⁺ cells while more DCX⁺ cells are present in hTM-DTA^iPet1 mice. Data were compared using Student’s t-test (p = 0.041 in g). All data are presented as mean ± s.e.m. *p < 0.05. Scale bars represent 100 μm (b,e).